Garmin Fish Finder 250 User Manual
Fishfinder 250/250C  
high-resolution sonar  
owner’s manual  
(Fishfinder 250C shown)  
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Preface  
Introduction  
Thank you for choosing the Garmin Fishfinder 250/250C. This product is designed for easy operation  
and to provide years of reliable service.  
Operations for the Fishfinder 250 and Fishfinder 250C are the same unless othewise noted. To ensure  
that you get the most from the Fishfinder 250/250C, please take the time to read this Owner’s Manual and  
learn the operation of your new unit. This manual is broken down into three sections. Section One covers the  
installation and testing for the Fishfinder 250/250C. Section Two provides detailed references to the features  
and operations of the Fishfinder 250/250C. Section Three gives a basic overview of how sonar works and  
provides information on interpreting the sonar graph.  
Preface and  
Registration  
Product Support  
If you encounter a problem or just have a question, our Product Support Department can be reached  
Monday-Friday 8am to 5pm Central Time.  
By phone at— 1-800-800-1020 or (913)397-8200  
Online at— http://www.garmin.com/contactUs/techSupport.jsp  
Check the Garmin Web Site (www.garmin.com) for links to Product Support and Product FAQ’s  
Enjoy your new Fishfinder 250/250C and once again thank you for choosing Garmin.  
Product Registration  
Help us better support you by completing our on-line registration today! Connect to our web site  
(www.garmin.com) and look for the Product Registration link on the Home page. Your unit’s serial number is  
located on the back of the unit.  
NOTE: If you have previously registered a Garmin product purchase, we invite you to re-  
register using our on-line system. Many services provided by our product registration system  
are now automated and re-registering your purchase ensures you the best possible support  
from Garmin.  
)
i
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LIMITED WARRANTY  
Introduction  
This Garmin product is warranted to be free from defects in materials or workmanship for one year from  
the date of purchase. Within this period, Garmin will at its sole option, repair or replace any components  
that fail in normal use. Such repairs or replacement will be made at no charge to the customer for parts or  
labor, provided that the customer shall be responsible for any transportation cost. This warranty does not  
cover failures due to abuse, misuse, accident or unauthorized alteration or repairs.  
THE WARRANTIES AND REMEDIES CONTAINED HEREIN ARE EXCLUSIVE AND IN LIEU OF ALL  
OTHER WARRANTIES EXPRESS OR IMPLIED OR STATUTORY, INCLUDING ANY LIABILITY ARISING  
UNDER ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, STATU-  
TORY OR OTHERWISE. THIS WARRANTY GIVES YOU SPECIFIC LEGAL RIGHTS, WHICH MAY VARY  
FROM STATE TO STATE.  
IN NO EVENT SHALL GARMIN BE LIABLE FOR ANY INCIDENTAL, SPECIAL, INDIRECT OR  
CONSEQUENTIAL DAMAGES, WHETHER RESULTING FROM THE USE, MISUSE, OR INABILITY TO  
USE THIS PRODUCT OR FROM DEFECTS IN THE PRODUCT. Some states do not allow the exclusion of  
incidental or consequential damages, so the above limitations may not apply to you.  
Garmin retains the exclusive right to repair or replace the unit or software or offer a full refund of the  
purchase price at its sole discretion. SUCH REMEDY SHALL BE YOUR SOLE AND EXCLUSIVE REMEDY  
FOR ANY BREACH OF WARRANTY.  
Warranty and  
Serial Number  
Serial Number  
Use this area to record the serial number (8-digit number  
located on the back of the unit) in case it is lost, stolen, or  
needs service. Be sure to keep your original sales receipt in a  
safe place or attach a photocopy inside the manual.  
Serial Number:  
*
*
To obtain warranty service, contact your local Garmin authorized dealer. Or call Garmin Customer Ser-  
vice at one of the numbers shown below, for shipping instructions and an RMA tracking number. The unit  
should be securely packed with the tracking number clearly written on the outside of the package. The unit  
should then be sent, freight charges prepaid, to any Garmin warranty service station. A copy of the original  
sales receipt is required as the proof of purchase for warranty repairs.  
Products sold through online auctions are not eligible for rebates or other special offers from Garmin.  
Online auction confirmations are not accepted for warranty verification. To obtain warranty service, an  
original or copy of the sales receipt from the original retailer is required. Garmin will not replace missing  
components from any package purchased through an online auction.  
,
The Fishfinder 250/250C is fastened shut with screws. Any  
attempt to open the case to change or modify the unit in any  
way will void your warranty and may result in permanent  
damage to the equipment.  
Garmin International, Inc.  
1200 East 151st Street  
Olathe, Kansas 66062, U.S.A.  
Phone: 913/397.8200  
Garmin (Europe) Ltd.  
Unit 4, The Quadrangle, Abbey Park Industrial Estate  
Romsey, SO51 9DL, U.K.  
Phone: 44/1794.519944  
ii  
FAX:  
913/397.0836  
FAX:  
44/1794.519222  
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Software License Agreement  
Introduction  
BY USING THE FISHFINDER 250/250C, YOU AGREE TO BE BOUND BY THE TERMS AND CONDI-  
TIONS OF THE FOLLOWING SOFTWARE LICENSE AGREEMENT. PLEASE READ THIS AGREEMENT  
CAREFULLY.  
Software License Agreement  
Garmin grants you a limited license to use the software embedded in this device (the “Software”) in binary  
executable form in the normal operation of the product. Title, ownership rights and intellectual property  
rights in and to the Software remain in Garmin.  
You acknowledge that the Software is the property of Garmin and is protected under the United States of  
America copyright laws and international copyright treaties. You further acknowledge that the structure,  
organization and code of the Software are valuable trade secrets of Garmin and that the Software in source  
code form remains a valuable trade secret of Garmin. You agree not to decompile, disassemble, modify,  
reverse assemble, reverse engineer or reduce to human readable form the Software or any part thereof, or to  
create any derivative works based on the Software. You agree not to export or re-export the Software to any  
country in violation of the export control laws of the United States of America.  
,
WARNING: This product, its packaging, and its components contain chemicals known to the State of  
California to cause cancer, birth defects, or reproductive harm. This Notice is being provided in accordance  
with California’s Proposition 65. If you have any questions or would like additional information, please refer  
to our web site at http://www.garmin.com/prop65.  
iii  
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Introduction  
Before installing and getting started with your unit, please check to see that your package includes the  
following items. The package part number can be found on the outside of the box. If any parts are  
missing, please contact your Garmin dealer immediately.  
Packing List  
Fishfinder 250 Standard Package (010-00343-00 w/o transducer):  
• Fishfinder 250 Unit • Swivel Mount Bracket and Knobs • Power/Data Cable • Owner’s Manual  
• Self-Adhesive Quick Reference Guide • Protective Cover • Flush-Mount Hardware Kit  
Fishfinder 250 Optional Package (010-00343-01) includes Standard Package, plus:  
• Dual Frequency (200/50kHz, 10/40°) Plastic Transom Mount Transducer with Depth and Temp  
Fishfinder 250 Optional Package (010-00343-02) includes Standard Package, plus:  
• Single Frequency (200kHz, 14°) Plastic Transom Mount Transducer with Depth and Temp  
Fishfinder 250C Standard Package (010-00341-00 w/o transducer):  
)
• Fishfinder 250C Unit • Swivel Mount Bracket and Knobs • Power/Data Cable • Owner’s Manual  
• Self-Adhesive Quick Reference Guide • Protective Cover • Flush-Mount Hardware Kit  
For the most recent list of available accessories for your  
unit, current user manuals and software updates, visit our  
web site at www.garmin.com.  
Fishfinder 250C Optional Package (010-00341-01) includes Standard Package, plus:  
• Dual Frequency (200/50kHz, 10/40°) Plastic Transom Mount Transducer with Depth and Temp  
• Separate Speed Sensor  
Fishfinder 250C Optional Package (010-00341-02) includes Standard Package, plus:  
• Single Frequency (200kHz, 14°) Plastic Transom Mount Transducer with Depth and Temp  
• Separate Speed Sensor  
Optional Accessories:  
• Quick-Release Flush Mount Bracket; US A/C PC Adapter; EURO A/C PC Adapter; Cigarette Lighter  
Adapter; 2nd Mounting Station; 10 ft. Transducer Extension cable; 20 ft. Transducer Extension cable;  
Temperature probe; Speed sensor; Plastic, thru-hull mount, Temp & Speed sensor only.  
iv  
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Introduction  
Transducers  
The transducer acts as the eyes and ears of your sonar, transmitting sound waves toward the bottom in a  
cone shape. Proper transducer selection and installation are important to the operation of your unit. It is best  
to select a transducer that suits the depth of the water that you are on.  
Selecting a Transducer  
A wide cone angle transducer works best in shallower water, providing a large coverage or viewing area,  
but at a decreased bottom resolution. In deep water this can result in a large area where fish cannot be seen.  
A narrow cone angle transducer is better suited to deep water installations, providing a smaller coverage  
or viewing area than a wide cone transducer, but with improved bottom resolution and a smaller dead zone.  
Optional Transducers:  
Included in the Optional Packages (p. iv) are transom mount transducers and separate speed sensors.  
These transducers provide good all-around performance. In addition, a variety of optional transducers are  
available from your local dealer or direct from Garmin.  
Wide cone angle  
• 200/50kHz, 12/45°, plastic, transom mount, depth, temp  
• 200/50kHz, 12/45°, plastic, transom mount, depth, temp, speed  
• 200/50kHz, 12/45°, bronze, thru-hull mount, depth  
• 200/50kHz, 12/45°, bronze, thru-hull mount, depth, temp, speed  
• 200/50kHz, 12/45°, bronze, thru-hull mount/long stem, depth, temp, speed  
• 200/50kHz, 12/45°, plastic, thru-hull mount, depth  
• 200/50kHz, 12/45°, plastic, adjustable. in-hull mount  
• 200kHz, 14°, plastic, transom mount, depth  
Narrow cone angle  
dead zone  
X
fish not seen  
• 200kHz, 14°, plastic, transom mount, depth, temp  
• 200kHz, 14°, plastic, transom mount, depth, temp, speed  
• 200kHz, 8°, plastic, transom mount, depth, temp  
• 200kHz, 8°, plastic, transom mount, depth, temp, speed  
• 200kHz, 12°, bronze, thru-hull mount, depth  
X
• 200kHz, 12°, bronze, thru-hull mount, depth, temp  
• 200kHz, 9°, bronze, thru-hull mount, depth, temp, speed  
• 200kHz, 12°, plastic, thru-hull mount, depth  
• 200kHz, 12°, plastic, thru-hull mount, depth, temp  
• 200kHz, 14°, plastic, in-hull mount, depth  
v
• 200kHz, 14°, plastic, trolling motor mount, depth, temp  
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Simulator . . . . . . . . . . . . . . . . . . . . . . . . .20  
NMEA Input/Output . . . . . . . . . . . . . . . .20  
Factory Settings . . . . . . . . . . . . . . . . . . . .20  
Software Version . . . . . . . . . . . . . . . . . . . .20  
Reset Odometer . . . . . . . . . . . . . . . . . . . .20  
Units Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . .20  
Depth . . . . . . . . . . . . . . . . . . . . . . . . . . . .20  
Temperature . . . . . . . . . . . . . . . . . . . . . . .20  
Distance and Speed . . . . . . . . . . . . . . . . .20  
Position Format . . . . . . . . . . . . . . . . . . . .20  
Heading . . . . . . . . . . . . . . . . . . . . . . . . . .21  
Sonar Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . .21  
Water Type . . . . . . . . . . . . . . . . . . . . . . . .21  
Depth Number . . . . . . . . . . . . . . . . . . . . .21  
Automatic Scroll Speed Limit . . . . . . . . . .21  
Keel Offset . . . . . . . . . . . . . . . . . . . . . . . .21  
Transducer Type . . . . . . . . . . . . . . . . . . . .21  
Calibrate Water Speed . . . . . . . . . . . . . . .21  
Time Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . .22  
Time Format . . . . . . . . . . . . . . . . . . . . . . .22  
Time Zone . . . . . . . . . . . . . . . . . . . . . . . .22  
Daylight Saving Time . . . . . . . . . . . . . . . .22  
Current Time and Date . . . . . . . . . . . . . . .22  
Depth Line . . . . . . . . . . . . . . . . . . . . . . . .14  
Noise Reject . . . . . . . . . . . . . . . . . . . . . . .14  
Scroll . . . . . . . . . . . . . . . . . . . . . . . . . . . .14  
Size Split . . . . . . . . . . . . . . . . . . . . . . . . . .14  
Pausing the Sonar Page . . . . . . . . . . . . . . . . . .15  
Main Menu . . . . . . . . . . . . . . . . . . . . . . . . . . .16  
Graph Tab . . . . . . . . . . . . . . . . . . . . . . . . . . .16  
Fish Symbols . . . . . . . . . . . . . . . . . . . . . .16  
Scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16  
Custom Range . . . . . . . . . . . . . . . . . . . . .16  
Background Color . . . . . . . . . . . . . . . . . .17  
Number Size . . . . . . . . . . . . . . . . . . . . . . .17  
Temperature and Water Speed . . . . . . . . .17  
Tools Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . .17  
Flasher . . . . . . . . . . . . . . . . . . . . . . . . . . .17  
Color Bar . . . . . . . . . . . . . . . . . . . . . . . . .17  
Temperature Graph . . . . . . . . . . . . . . . . .17  
Advanced Data Fields . . . . . . . . . . . . . . . .17  
Temp Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . .18  
Log and Graph Scale . . . . . . . . . . . . . . . . .18  
Reset (Scale) . . . . . . . . . . . . . . . . . . . . . . .18  
Log Duration . . . . . . . . . . . . . . . . . . . . . .18  
Alarms Tab . . . . . . . . . . . . . . . . . . . . . . . . . . .19  
Fish Alarm . . . . . . . . . . . . . . . . . . . . . . . .19  
Shallow/Deep Water Alarms . . . . . . . . . . .19  
Drift Alarm . . . . . . . . . . . . . . . . . . . . . . . .19  
Water Temperature Alarm . . . . . . . . . . . . .19  
Battery Alarm . . . . . . . . . . . . . . . . . . . . . .19  
Timer Alarm . . . . . . . . . . . . . . . . . . . . . . .19  
System Tab . . . . . . . . . . . . . . . . . . . . . . . . . . .20  
Beeper . . . . . . . . . . . . . . . . . . . . . . . . . . .20  
Display Mode . . . . . . . . . . . . . . . . . . . . . .20  
Language . . . . . . . . . . . . . . . . . . . . . . . . .20  
Introduction  
Table of Contents  
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . i-vi  
Preface and Registration . . . . . . . . . . . . . . . . . . i  
Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . .ii  
Software License Agreement . . . . . . . . . . . . . . iii  
Packing List . . . . . . . . . . . . . . . . . . . . . . . . . . iv  
Selecting a Transducer . . . . . . . . . . . . . . . . . . .v  
Table of Contents . . . . . . . . . . . . . . . . . . . . . . vi  
Section One: Installation . . . . . . . . . . . . . . . . . 1-9  
Unit Installation . . . . . . . . . . . . . . . . . . . . . . . .1  
Wiring and Interfacing . . . . . . . . . . . . . . . . . . .5  
Mounting the Transducer . . . . . . . . . . . . . . . . .7  
Testing the Installation . . . . . . . . . . . . . . . . . . .9  
Section Two: Unit Operation . . . . . . . . . . . . 10-22  
Keypad Usage . . . . . . . . . . . . . . . . . . . . . . . . .10  
Sonar Page . . . . . . . . . . . . . . . . . . . . . . . . . . .11  
Using the Adjustment Menu . . . . . . . . . . . . . .12  
Adjustment Menu Options . . . . . . . . . . . . . . .12  
Range . . . . . . . . . . . . . . . . . . . . . . . . . . . .12  
Zoom . . . . . . . . . . . . . . . . . . . . . . . . . . . .12  
View/Span . . . . . . . . . . . . . . . . . . . . . . . .13  
Gain . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13  
Target Level . . . . . . . . . . . . . . . . . . . . . . .13  
Whiteline . . . . . . . . . . . . . . . . . . . . . . . . .14  
Frequency . . . . . . . . . . . . . . . . . . . . . . . . .14  
Section Three: On the Water . . . . . . . . . . . . 23-26  
Understanding Sonar . . . . . . . . . . . . . . . . . . .23  
Transducer Coverage . . . . . . . . . . . . . . . . . . .24  
Understanding the Graph . . . . . . . . . . . . . . . .25  
Whiteline and Thermoclines . . . . . . . . . . . . .26  
Appendices . . . . . . . . . . . . . . . . . . . . . . . . . 27-30  
Appendix A: Specifications and Cleaning . . . .27  
Appendix B: Messages and Alarms . . . . . . . . .28  
Appendix C: Index . . . . . . . . . . . . . . . . . . . . .29  
vi  
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Installing the Fishfinder 250/250C  
Installation  
The Fishfinder 250/250C must be properly installed according to the following instructions to get the  
best possible performance. To complete the installation, you’ll need the appropriate fasteners and tools.  
Verify that all cables can reach the unit mounting location and also take time to read through these instruc-  
tions prior to installation. Be sure to always wear safety goggles and a dust mask when drilling, cutting or  
sanding. When in doubt, seek professional assistance.  
Unit Installation  
Selecting a Proper Location  
Choose a location that provides optimal viewing while operating the vessel and allows easy access to  
the unit’s keypad. Select a mounting surface strong enough to support the weight of the unit and protect  
it from excessive vibration and shock. DO NOT mount the bracket in a location where the unit is exposed  
to extreme temperature conditions. When installing the mounting bracket, be sure to allow room for the  
connection/routing of the power and transducer cables.  
Swivel Mounting the Fishfinder 250/250C Unit  
The Fishfinder 250/250C’s compact, waterproof case is suitable for mounting in exposed locations or  
at the nav station. The unit comes with a swivel-mount bracket that can be used for console or overhead  
mounting. When choosing a location for the display unit, make sure you consider the following conditions:  
•
There should be at least a 3” (8 cm) clearance behind the case to allow connection of the transducer  
and power/data cables.  
•
The mounting surface should be sturdy enough to support the unit and protect it from excessive  
vibration and shock.  
NOTE: The temperature range for the Fishfinder 250/250C is 5°F to 130°F (-15°C to 55°C).  
,
Extended exposure to temperatures exceeding this range (in storage or operating condi-  
tions) may cause failure of the LCD screen. This type of failure and related consequences are  
NOT covered by the manufacturer’s limited warranty.  
1
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To swivel mount the Fishfinder 250/250C display:  
Installation  
Tools (not included) — Drill, Screwdriver (Phillips or Standard), three #8 (4mm) pan head machine bolts  
with matching nuts and washers and a 5/32” (5mm) drill bit, OR three #8 pan head self-tapping screws and  
an appropriately-sized drill bit for drilling starter holes.  
Unit Installation  
1. Using the swivel base as a template, mark the location of the three holes that are used to secure the  
bracket to the mounting surface.  
2. If securing the base with machine bolts, drill three 5/32” (5mm) holes at the locations you marked. OR,  
if securing the base with self-tapping screws, drill starter holes at the locations you marked. Starter holes  
should generally be no deeper than half the screw length.  
3. Secure the swivel base with three bolts or screws. DO NOT OVERTIGHTEN.  
4. Place the rest of the mount over the swivel base and secure with the short knob.  
OK  
The swivel base is designed to be secured using a pan  
head screw or machine bolt. If you use a screw with a  
countersunk head, you risk damaging the Mounting  
Bracket.  
Secure the base and attach the mount  
2
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Installing the Unit on the Mounting Bracket  
Installation  
1. Align the slot on the back of the unit with the long mounting knob and slide in place. It may be neces-  
sary to adjust the long mounting knob to spread the bracket arms apart. (Turn counter-clockwise to  
widen the bracket arms, clockwise to tighten.)  
Unit Installation  
2. Adjust the unit angle and tighten the long mounting knob until snug.  
3. To tilt the unit, loosen the long mounting knob on the right side of the bracket assembly.  
4. To rotate the entire bracket, twist it left or right. The bracket clicks as you turn it.  
5. Tighten all knobs once the desired viewing angle is obtained.  
Adjust for optimal viewing  
Slide the unit onto the bracket  
3
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Flush Mounting the Fishfinder 250/250C Unit  
Installation  
The Fishfinder 250/250C can be flush mounted on a flat panel. When flush mounting the Fishfinder  
250/250C, be sure to choose an appropriately sized location for the unit. Check that all cables reach the  
unit mounting location before beginning installation. Use the Flush Mount Template provided in the box to  
determine a location. Always wear safety goggles and a dust mask when drilling, cutting or sanding.  
Unit Installation  
To flush mount the Fishfinder 250/250C:  
Included Mounting Hardware — 4 - 3mm Studs, 4 - Flat Washers, 8 - 3mm Hex Nuts.  
Tools (not included) — Center Punch, Drill, 1/8” (3mm) Drill Bit, 3/8” (6mm) Drill Bit, Jig Saw, 1/16”  
(2mm) Allen Wrench, 9/35” (7mm) Wrench.  
1. Trim the Flush Mount Template and tape in the desired location.  
2. Using a Center Punch, indent the center of each Mounting Hole location.  
3. Using a 1/8” (3mm) drill bit, drill the four Mounting Holes.  
Hex Nuts  
Washer  
Studs  
4. Using a 3/8” (6mm) drill bit, drill a hole for a location to begin cutting the mounting surface.  
5. Using the Jig Saw, cut the mounting surface along the inside of the dashed line indicated on the  
template. Be very careful when cutting this hole, there is only a small amount of clearance  
between the unit and the Mounting Holes. It may be prudent to cut slightly inside the indicated  
line and then sand or file the panel as needed to obtain the best fit.  
6. Install the four Mounting Studs into the unit by screwing the shorter section into the back of the unit.  
Use a 1/16” (2mm) Allen Wrench to tighten the Mounting Studs until the stops contact the case. Be  
careful not to overtighten as this may damage the Mounting Stud. The studs have a reusable thread-  
locking patch pre-applied from the factory.  
7. Place the unit in position inside the cutout area of the mounting surface.  
8. Place washers over the Mounting Studs, then thread on one Hex Nut per Mounting Stud. Tighten all four  
Hex Nuts until the unit is snug against the mounting surface. Install and tighten the second Hex Nut on  
all four Mounting Studs to lock the first Hex Nut in place.  
4
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Connecting the Power/Data Cable  
Installation  
The power/data cable connects the Fishfinder 250/250C to a 10-35 volt DC system and provides  
interface capabilities for connecting external devices. The color code in the diagram (pg. 6) indicates the  
appropriate harness connections. If it is necessary to extend the power/data wires, use a wire of comparable  
size and keep your extension as short as possible.  
Wiring and Interfacing  
To 10-35 Volt Boat Supply  
The unit can be wired directly to your boat’s battery or to an unused holder on your boat’s fuse block.  
When connecting the unit directly to the battery, make sure the 2-Amp in-line fuse supplied with the unit is  
installed . If needed, use an ACG/3AG - 2 Amp replacement fuse. If you decide to use the fuse block, remove  
the in-line fuse holder supplied with the unit.  
Installing the Wiring Harness (Basic):  
+
1. Determine the polarity of the fuse holder using a Test Light or Volt Meter.  
2. Install the Red (+) wire on the Positive Fuse Holder Terminal.  
3. Install the Black (-) wire on the Negative Fuse Holder Terminal.  
4. Install a 2 amp fuse in the Fuse Holder.  
Install 2-Amp  
Fuse  
The Fishfinder 250/250C can be connected to another piece of NMEA compatible electronic equipment,  
such as a Garmin GPS (Global Positioning System). If equipped with a capable transducer, the Fishfinder  
250/250C can send depth, temperature, and speed information to the NMEA device. It can also mark a  
location (pg. 15) that could be displayed on another device and can accept GPS navigational data (pg. 17),  
such as position, time, course, distance, etc. Refer to the wiring diagram on the following page for interfac-  
ing the Fishfinder 250/250C with other devices.  
-
Boat Ground  
Installing the Wiring Harness to a GPS or other NMEA device:  
1. Follow steps 1-4 of the above wiring harness installation. For Garmin units, the Ground (black) wires  
from both devices must be attached together or on the same fuse terminal for data ground. Refer to the  
wiring diagram of your GPS unit for wire identification.  
2. Connect the Blue (Data Out) wire from the Fishfinder to the Data IN wire on the GPS/NMEA harness.  
3. Connect the Brown (Data In) wire from the Fishfinder to the Data OUT wire on the GPS/NMEA harness.  
To Fishfinder 250/250C  
4. Set the Fishfinder 250/250C NMEA Input/Output to ‘On’ (pg. 20). For Garmin GPS units, set the  
communications interface to NMEA/NMEA, NMEA In/NMEA Out or NMEA.  
5
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To Transducer  
(TX COM 2)  
(RX COM 2)  
(RX COM 1)  
Installation  
DC Positive  
(TX COM 1)  
(red) + 10-35 VDC  
Wiring and Interfacing  
Power  
10-35 volts  
(black) - Ground (Power/Data)  
(blue) Port 1 Data OUT  
To Unit  
(brown) Port 1 Data IN  
RXD +  
GPS/NMEA  
Device  
(white) Port 2 Data IN (N/C)  
TXD +  
You can download a copy of Garmin's proprietary  
communication protocol document from the Support  
section of our web site at www.garmin.com.  
(green) Port 2 Data OUT  
and RXD -  
NMEA Device  
(yellow) Alarm Low  
Alarm Relay  
Note: During a typical installation, only the Red and  
Black wires are used. The other wires do not have to  
be connected for normal operation of the unit.  
RXD +  
100ma max  
coil current  
Complete information concerning  
National Marine Electronics Association  
(NMEA) format and sentences is avail-  
able for purchase from NMEA at:  
NMEA  
Interfacing  
The Fishfinder 250/250C allows for NMEA 0183, Version 2.3 input/output with a compatible GPS or  
navigation device. NMEA Input/Output must be set to ‘On’ to send/receive data (see pg. 20). For additional  
information on using your Fishfinder 250/250C with NMEA devices, see pages 5, 15, and 20.  
Seven Riggs Avenue  
Severna Park, MD 21146  
U.S.A.  
410-975-9425  
410-975-9450 FAX  
The following are the sentences for NMEA 0183, version 2.3:  
Input — GPBOD, GPBWC (only used if RMB not present), GPGGA, GPGLL (only used if GGA not present),  
GPRMB, GPRMC, GPXTE (only used if RMB not present)  
Output — SDDBT, SDDPT, SDMTW, SDVHW, SDWPL* (only if a waypoint is “marked” in Pointer Mode)  
www.nmea.org  
*Garmin GPS units will accept the SDWPL (WPL) NMEA sentence and create a waypoint (saved location) at that position (see  
pg. 15). For compatibility with other brands of GPS or NMEA capable navigation devices, check with that manufacturer to see if their  
unit accepts/stores NMEA 0183 SDWPL sentences/waypoints. The Fishfinder 250/250C does not store the actual waypoint. Only the  
6
receiving device, if capable, will store the waypoint.  
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Installing the Transducer  
Installation  
Proper transducer installation is key to getting the best performance from your new unit. If the trans-  
ducer lead is too short, extension cables are available from your Garmin dealer. Coil and secure any excess  
cable. DO NOT cut the transducer lead or any part of the transducer cable, as this will void your warranty.  
The cable cannot be spliced and connected to any existing (Garmin or non-Garmin) transducer cables.  
Mounting the Transducer  
Following are some tips and basic installation instructions for some popular transducers. Detailed  
installation instructions are provided in the transducer kits. Some transducers may need to be  
installed by a professional marine installer.  
,
DO NOT mount the transducer behind strakes,  
struts, fittings, water intake or discharge ports,  
or anything that creates air bubbles or causes the  
Transom Mount Installation  
To Unit  
Transom Mount Transducer  
(depth/temp)  
USS Jayhawk  
water to become turbulent. It is important that the  
transducer be in clean (non-turbulent) water for  
optimal performance.  
Mount the transducer cable cover  
well above the waterline.  
Apply marine sealant to all  
screw threads to prevent water  
from seeping into the transom.  
Transducer should extend 1/8" (3mm) below  
fiberglass hull or 3/8" (10mm) below aluminum hull  
Make sure that the transducer is  
Speed  
Temp Transducer  
below water level when the boat  
OK  
is on plane at high speed  
Connecting a Transducer to Multiple Sensors  
Do not mount transducer directly in the  
path of the prop. The transducer can cause  
cavitation that may degrade the boat's performance  
and damage the prop.  
Mount the transducer parallel with the bottom.  
7
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Shoot-Thru-Hull Installation  
Installation  
To avoid drilling a hole to mount a thru-hull transducer, a transducer may be secured with epoxy inside  
a boat (“shoot-thru-hull” installation). This type of installation can provide better noise reduction and allow  
you to use a higher gain setting. For a transducer to be mounted inside the hull (shoot-thru, not thru-hull),  
the boat must be fiberglass, with no core. Contact your boat manufacturer if you are unsure. Professional  
installation may be necessary. Be sure to always wear a dust mask and safety goggles when installing.  
Mounting the Transducer  
Some transducers are specifically designed to be mounted inside a fiberglass hull. The standard plastic  
transom mount transducer can also be mounted in this fashion using the following method. If using a  
temperature sensing transducer, the temperature displayed reflects the hull temperature.  
Selecting a location:  
1. The location has to be solid fiberglass, devoid of any air bubbles, laminates, fillers or dead air space. The  
location needs to be in an area of clean water at all speeds. Do not place the transducer over any strakes  
or behind any obstruction on the hull that would create turbulence at speed.  
Weight transducer  
to hold it in place  
PVC Pipe  
or a Can  
NOTE: Many modern hulls have a prelocated pocket for shoot-thru-hull transducer  
installation. If you are unsure if your hull is equipped with a pre-located pocket,  
contact your hull manufacturer.  
)
Fill Pipe or Can  
with water or a  
light mineral oil  
Strip Caulk  
or RTV Sealer  
Testing the location:  
1. Fabricate a test device from a section of PVC pipe or a can, as shown in the side bar.  
Hull Surface  
Testing the Location  
2. Temporarily seal the test device to the hull with caulking or RTV sealer, and fill with water or light  
mineral oil.  
3. Place the transducer in the water, pointed directly at the bottom. Weight it down. Set unit for optimum  
performance. If the sonar performance is significantly degraded, find and test another location.  
Permanently installing the transducer:  
1. Lightly sand the surface of the hull and face of the transducer with 400 grit wet or dry sandpaper.  
2. Build a dam using strip caulk about 1/4” (6mm) tall. Pour about 1/8” (3mm) of two part, slow cure  
epoxy in the dam.  
3. Place the transducer in the epoxy, turning the transducer to work out any air bubbles.  
4. Weight the transducer in place and allow to cure for 24 hours.  
8
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Testing the Installation  
Installation  
While it is possible to perform some checks with the boat trailered, the boat should be in the water to  
properly test the sonar portion of the installation.  
Press the POWER/BACKLIGHT key (see pg. 10) and the Fishfinder 250/250C should power on. If the  
unit fails to power on, verify that the wiring adapter is seated properly in the back of the unit, the Red and  
Black wires are connected to the correct polarity, and that the 2-Amp fuse is installed and not blown. If the  
unit is connected to a power supply that exceeds 35 volts DC, a “Battery Voltage High” warning is displayed  
and the unit turns off. If the unit does not detect a transducer, it automatically enters Simulator Mode.  
Testing the Installation  
When the unit detects a transducer on initial power up, a “Please set up transducer” message is dis-  
played. Press the ENTER key (see pg. 10) to select the transducer type. Highlight your transducer type with  
the ARROW keys and press ENTER. Press ADJ/MENU to return to the Sonar display.  
Since water is necessary to carry the sounder’s sonar signal, the transducer must be in the water to work  
properly. It is not possible to get a depth/distance reading when out of the water. As the unit powers on, it  
should immediately start showing the bottom. Verify that the unit is not in the simulator mode. If the unit  
is in the simulator mode, make sure that the transducer is connected properly to the unit. When you place  
your boat in the water CHECK FOR LEAKS around any screw holes that have been added below the water  
line. DO NOT leave your boat in the water for an extended period of time without checking for leaks.  
Begin testing the installation at a slow speed. If the sonar appears to be working properly, gradually  
increase the boat’s speed while observing the sonar’s operation. If the sonar signal suddenly is lost or the  
bottom return is severely degraded, note the speed at which this occurs. Return the boat to the speed the  
signal was lost. Make moderate turns in both directions and see if the signal improves. If the signal strength  
improves while turning, adjust the transducer so that it extends another 1/8" (3mm) below the transom of  
the boat. It may take several adjustments to eliminate the degradation. If the signal does not improve, it may  
be necessary to move the transducer to a different location.  
NOTE: When adjusting the depth of the transducer, make the adjustments in small incre-  
ments. Placing the transducer too deep can adversely affect the boat’s performance and put  
)
the transducer at greater risk of striking underwater objects.  
9
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Using the Keypad  
Unit Operation  
The keypad contains the following keys:  
Keypad Usage  
ARROW Keys— used to select (highlight) menu options and enter data. Also control movement of the  
cursor when paused in Pointer mode. Allow direct control of Sonar Page Adjustments.  
ENTER Key— selects a highlighted menu option. When entering data, allows you to initiate entry and then  
accept the selected value(s). When paused in Pointer mode, press to create a waypoint at the Pointer position  
(if interfaced with compatible NMEA GPS).  
ADJ/MENU Key— from the sonar screen, press and release to display the Adjustment Menu. Press and hold  
to access the Main Menu for unit configuration. From either menu, press and release to return to the sonar  
page.  
ADJ  
MENU  
POWER/BACKLIGHT Key— press and hold to turn the unit on and off. While the unit is on, press and  
release to display the light/contrast adjustment window.  
To change the backlight/contrast settings:  
1. Press and release POWER/BACKLIGHT to display the light/contrast adjustment window. The adjustment  
window automatically disappears when idle for 20 seconds.  
2. Press the UP or DOWN ARROW keys to change the backlight setting. Press and release  
POWER/BACKLIGHT to toggle the backlight setting between maximum, user-set, and minimum  
brightness levels.  
)
3. Press the LEFT or RIGHT ARROW keys to change the contrast setting.  
4. Press ENTER to return to the Sonar Page.  
NOTE: Always press and release a key to perform  
its primary function. Pressing and holding a key will  
activate its secondary function (if available).  
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Sonar Page  
Unit Operation  
The Sonar Page is where your Fishfinder 250/250C becomes a powerful fishfinder/flasher. If the unit  
does not detect a transducer, a “Sonar Turned Off” message is displayed on the Sonar Page. If in Simulator  
mode, a “Running Simulator” message is displayed.  
Understanding the Display  
The currently selected Adjustment option (see pg. 12) is displayed in the top left of the screen. Directly  
below the Adjustment option, the screen displays numeric data such as Depth, Water Temperature and  
Water Speed (see pg. 17-18). The middle of the page contains a right-to-left moving sonar image of the  
water beneath your boat. (NOTE: Items appear as they pass under your transducer. Items on the right side  
of the screen are closer to you than those on the left.) Along the right side of the screen is a scale which  
reflects the depth of the area being displayed.  
Current  
Adjustment  
Option  
Depth  
Scale  
Fish Arches  
(Simulated)  
Numeric  
Data  
Flasher  
The display may also be set to show a split screen view of a zoomed portion of the sonar, bottom lock  
(display scaled from the bottom up), or a combination of these options (see pg. 13). For example, you may  
choose to show dual frequency at a 2X zoom (Dual 2X) on one half of the screen, with normal range dual  
frequency (Dual) on the other half. The current display mode is shown at the bottom of each sonar display.  
Bottom  
Thermocline  
The Fishfinder 250 displays sonar returns as shades of gray; stronger returns are darker, and weaker  
returns are lighter. On the Fishfinder 250C, sonar returns are displayed as red (strongest), then orange  
(strong), yellow (medium), green (weaker) and blue (weakest).  
The ‘Fish Symbols’ option (see page 16) allows you to find fish by viewing the actual sonar data, a fish  
symbol or a combination of both. ‘Fish Symbols’ appear as black on the Fishfinder 250 and green on the  
Fishfinder 250C. When the unit is set to ‘Dual’ frequency mode (see page 14), the appearance of the fish  
symbols (and simulated fish returns) will change. Fish symbols from the narrower beam (200kHz) will be  
solid (narrow returns), but the returns from the wider beam (50kHz) will be hollow (wide returns). Simu-  
lated fish icons are displayed in three different sizes based on the size of the return. Actual fish returns may  
not always appear as perfect arches, due to the speed, fish orientation, and/or other conditions.  
Fish Symbol  
Narrow  
beam returns  
Wide beam  
returns  
Frequency  
mode  
For more information on understanding the sonar, see pages 23-25.  
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Using the Adjustment Menu  
Unit Operation  
The Adjustment Menu allows direct access to the settings and features most commonly used on the  
Sonar Page. There are 10 main adjustment options available: Range, Zoom, View, Gain, Target Level,  
Whiteline, Frequency, Depth Line, Noise Reject, and Scroll. All adjustments may be made by using the  
ARROW keys and ENTER key. The currently selected option will appear in the upper left of the display  
with an up and down arrow on each side of the name.  
Adjustment Menu Options  
To change an Adjustment Menu setting:  
1. Press ADJ/MENU to display a list of all options and their current settings. The adjustment window  
automatically disappears when idle for 20 seconds or you may press ADJ/MENU to exit.  
Current  
adjustment  
setting  
2. Press the UP or DOWN ARROW keys to highlight the desired option and press ENTER to display the  
Adjustment window.  
3. Press the UP or DOWN ARROW keys to move the setting bar (or pointer) to the desired percentage (Off,  
1-100%), setting or range. When changing most adjustments, an open space is displayed on the scale  
to indicate the ‘Normal’ or default setting. Once set to ‘Normal’, the setting bar is replaced by the word  
‘Normal’.  
‘Normal’  
setting  
area  
4. Press ENTER to accept the new setting and return to the Sonar Page.  
Adjustment Menu options  
The current adjustment option is displayed in the upper left corner of the screen. For fast adjustment  
from the Sonar Page, press the LEFT or RIGHT ARROW keys to scroll through the options, then press the  
UP or DOWN ARROW keys to immediately change the current option or press the ENTER key to review  
the current setting before making changes.  
Current option  
Adjustment  
window  
Adjustment Options  
The Adjustment Menu allows direct access to the settings and features most commonly used. These  
available adjustments are:  
Pointer  
• Range — sets the display depth range used for viewing. The unit can be set to automatically track the  
bottom or set to a user-specified depth range (see “Custom Range” pg. 16).  
• Zoom — used to quickly select a display zoom scale or to split the display. When a scale other than  
‘No Zoom’ is selected, the ‘View’ or ‘Span’ options are activated in the Adjustment Menu.  
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The Zoom function has seven settings:  
Unit Operation  
No Zoom –– Displays the sonar picture with no zoom.  
2x Split –– Shows two reduced-size sonar pictures at the same time. The right half of the display  
screen shows the complete sonar picture at its original scale. The left half shows a portion of the  
original picture at 1/2 depth scale.  
Adjustment Menu Options  
2x Zoom –– Displays the 2x zoomed picture on the full screen and does not show the original scale  
picture.  
4x Split –– Shows two reduced pictures, the right at the original depth scale and the left at 1/4 the  
original depth scale.  
Depth Line  
4x Zoom –– Displays only the 4x zoomed picture on the full screen.  
Btm (Bottom) Split –– Shows two reduced pictures, the right at the original depth scale and the  
left showing only sonar returns close to the bottom. The bottom is displayed as a flat line across the  
bottom of the screen, and returns are shown at their distance from the bottom up. You can adjust the  
scale of the Bottom Split display by changing the Span setting (see below).  
2x Zoom  
View  
Normal View  
Btm (Bottom) Lock –– Displays the Bottom Lock (returns close to the bottom, shown at their  
distance from the bottom up) picture on the full screen. You can adjust the scale of the Bottom Lock  
display by changing the Span setting (see below).  
Sonar 2x Split Screen  
(shown with Depth Line)  
• View/Span — available when a Zoom scale other than ‘No Zoom’ is selected. The ‘View’ or ‘Span’ set-  
ting is used to change the viewing range of a zoomed display. The ‘View’ option is enabled when the display  
is set to 2x Split, 2x Zoom, 4x Split, or 4x Zoom. If the display is 2x or 4x split, only the zoomed portion on  
the left side of the display is affected by the change. If the display is Bottom Split or Bottom Lock, the ‘Span’  
option is enabled to adjust how far off the bottom the unit displays data.  
• Gain — controls the sensitivity of the unit’s receiver. This provides some flexibility in what is seen on  
the display. To see more detail, increase the receiver sensitivity by selecting a higher gain percentage. If there  
is too much detail or if the screen is cluttered, lowering the sensitivity may increase the clarity of the display.  
Bar  
represents  
area shown  
on 2x View  
• Target Level — adjusts which colors (Fishfinder 250C) or shades of gray (Fishfinder 250) are used to  
display sonar information. A Color Bar (see pg. 17) is displayed on the right side of the screen as you adjust  
this setting. A higher percentage results in more strong-signaled colors or shades (see pg. 11) displayed on  
the Sonar Page. A lower percentage results in more weaker-signaled colors or shades (see pg. 11) displayed  
on the Sonar Page. This setting does not increase/decrease the unit Gain.  
Sonar View Adjustment  
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• Whiteline — controls how the unit displays information about the bottom type (hard or soft). With  
the Whiteline ‘Off’, all high-intensity bottom returns are displayed as red on the Fishfinder 250C and black  
on the Fishfinder 250. With Whiteline set at ‘Normal’ or 1-100%, this option can be used to better deter-  
mine bottom hardness. See page 26 for more information on this feature.  
• Frequency — allows you to choose a sonar operation frequency. Frequency refers to the “pitch” of the  
sound that the transducer sends and receives. You may choose ‘200kHz’, ‘50kHz’ or ‘Dual’ frequency (when  
using a dual frequency transducer).  
Unit Operation  
Adjustment Menu Options  
You may  
• Depth Line — adds a horizontal depth line across the display to measure the depth of underwater  
objects. The depth of the line is displayed in a box on the right side of the line. When the Depth Line adjust-  
ment window is visible, press the UP or DOWN ARROW keys to control the position of the line on the  
graph.  
resize the split  
line to the left  
or right.  
• Noise Reject — helps filter unwanted noise from the graph. The ‘Noise Reject’ tool can be turned  
‘Off’, set to ‘Normal’ (automatically adjusts for optimum viewing) or to a fixed 1-100% setting. NOTE: the  
HIGHER the noise rejection setting, the more likely the unit is to NOT show fish or structure.  
• Scroll — adjusts the rate that the graph scrolls from right to left. If you are sitting still or the graph is  
moving too fast, slowing the scroll rate or pausing it can be beneficial. ‘Auto’ automatically adjusts the scroll  
rate according to the boat’s speed. (See also ‘Automatic Scroll Speed Limit’ on page 21.)  
Resizing the Sonar Split  
• Size Split — enables width adjustment of the Sonar Page split screen. This option is only available  
when a split zoom is selected. You may adjust the size of the split window anywhere from 1/4 to 3/4 width  
from the right half of the Sonar Page.  
To resize the Sonar Page split screen:  
1. From the Sonar Page split screen, press ADJ/MENU.  
2. Using the ARROW keys, highlight the ‘Size Split’ option and press ENTER. A small double-arrow is  
displayed in the middle of the split line on the screen.  
3. Press the LEFT or RIGHT ARROW keys to move the split line to the desired position, then press ENTER.  
• Defaults — restores Adjustment Options back to original factory settings.  
The current frequency setting will  
display at the bottom of the screen.  
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Pausing the Sonar Page  
Unit Operation  
You may pause the Sonar Page to stop it from scrolling. The paused screen allows you to take a better  
look at sonar returns. When in this mode, the word “Paused” is displayed at the bottom of the screen and  
a Pointer cursor is activated. You may move the Pointer around on the paused sonar graph in order to  
reference sonar items and mark waypoints for that location (if attached to a Garmin GPS or compatible  
NMEA navigation device. See pg. 5.) A data field is displayed at the top of the graph with the Pointer’s  
depth, surface temperature for that position, and GPS coordinates (if available). This makes it easier to find  
and use objects such as stumps, rocks, or brush piles for future fishing locations. The depth continues to  
update while the display is paused, but the unit will not show any new sonar data until the Sonar display is  
unpaused (resumed). You may see a discontinuity from where the sonar information stops to where it starts  
again.  
Pausing the Sonar Page  
To pause and unpause the Sonar display:  
1. From the Sonar Page, press ADJ/MENU.  
2. Using the ARROW keys, highlight the ‘Pause’ option and press ENTER. The Sonar display is paused. The  
As you move the Pointer, the Depth,  
Temp and Position (if available) is  
displayed at the top of the screen.  
Pointer cursor is activated, and data fields for the Pointer are displayed at the top of the screen.  
3. To unpause the Sonar display, press ADJ/MENU, highlight the ‘Resume’ option and press ENTER.  
To mark an underwater waypoint:  
1. With the Sonar display paused, use the ARROW keys to move the cursor onto the target (underwater  
drop off, stump, etc.) you want to mark. A data field is displayed with the cursor’s depth, surface tem-  
perature for that position and GPS coordinates.  
3. Press ENTER. The New Waypoint window is displayed with a default three-digit name and pointer’s  
coordinates automatically filled in.  
4. To change the name, highlight the name field and press ENTER. Make your changes using the ARROW  
keys and press ENTER when done.  
5. When finished, move the field highlight back to the ‘OK’ prompt and press ENTER. The unit sends a  
NMEA WPL sentence to an attached GPS unit or NMEA navigational device (see pgs. 5-6).  
You may send an underwater  
waypoint to a GPS unit.  
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Main Menu  
Unit Operation  
The Main Menu contains the unit settings that usually do not require frequent change. The Main Menu  
is divided into eight tabs: Graph, Tools, Temp, Alarms, System, Units, Sonar and Time. Each tab is described  
in more detail in this section.  
Main Menu Options  
To enter the Main Menu, press and hold the ADJ/MENU key. The first time you enter the Main Menu,  
the ‘Graph’ tab is highlighted in black. Press the UP or DOWN ARROW keys to highlight different tab selec-  
tions. Press the RIGHT ARROW key to access the selection fields. Each time the Main Menu is accessed, the  
unit returns to the last edited selection field. Press the LEFT ARROW key to get back to the tabs.  
To change a setting on a Main Menu tab:  
1. Using the ARROW keys, highlight the desired field and press ENTER.  
2. Highlight the desired setting and press ENTER.  
3. Press ADJ/MENU to return to the Sonar display or to cancel data entry.  
Graph Tab  
Main Menu - Graph Tab  
The Graph Tab allows you to determine the appearance of the scrolling graph display and contains the  
unit settings that usually do not require frequent change.  
The following settings are available:  
Fish Symbols Off— All available information is  
displayed.  
•
Fish Symbols — allows you to determine how the graph shows underwater targets and back-  
ground information. If Fish Symbols are set to ‘Off’, the unit displays all of the available informa-  
tion about the underwater environment. If a fish symbol is selected, the graph displays only the  
information related to that symbol. Actual fish returns may not always appear as perfect arches (like  
in simulator mode), due to the speed, fish orientation and/or other conditions.  
Suspended targets are displayed as fish symbols.  
Background information is displayed.  
Same as above with the target depth attached.  
•
•
Scale — controls the presentation of the depth ‘Scale’ displayed vertically along the right side of the  
graph. The depth ‘Scale’ can be configured to display four different ways: ‘Overlay’, ‘Corners’, ‘Basic’  
or ‘No Scale’.  
Suspended targets are displayed as fish symbols. No  
background information is displayed.  
Same as above with target depth attached.  
Custom Range — allows you to specify a custom viewing range/scale. Once enabled, this range is  
displayed as ‘Custom’ in the ‘Range’ adjustment control. The left value is the top of the scale and the  
right value is the bottom of the scale.  
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Unit Operation  
•
•
•
Background Color (Fishfinder 250C only) — allows you to change the background color of the  
sonar display. Choices are Black, Blue or White.  
Number Size — allows you to choose between a Normal or Large sized Basic depth/temp/speed  
display. This does not change the Advanced data field number sizes.  
Main Menu Options  
Temperature and Water Speed — hides or displays temperature and water speed on the Sonar  
Page. When set to ‘Auto’, the unit automatically displays this information only if it is received from  
the transducer.  
Tools Tab  
Controls the display of useful sonar tools. The following settings are available:  
•
Flasher — this option activates a graphic Flasher representation, displayed on the right side of the  
graph. The graphic Flasher displays structure and bottom returns much the same as a true Flasher.  
You may find this feature particularly useful when using ‘Fish Symbols’ (see pages 11 and 16).  
•
•
Color Bar — shows a gradient scale of the current Target Level setting (see page 13).  
Main Menu - Tools Tab  
Temperature Graph — toggles On or Off the display of a temperature graph on the Sonar Page.  
•
•
Advanced Data Fields — toggles On or Off the Advanced data fields on the Sonar Page  
Configure Advanced Data Fields — activates the Advanced Data Field Setup screen  
Configuring Advanced Data Fields  
The top left of the screen contains configurable data fields for the sonar display. By default, the Basic  
display shows the depth, water temperature and speed (depending on the Graph Tab settings and type of  
transducer/sensors attached). The ‘Configure Advanced Data Fields’ option in the Tools Tab allows you to  
customize the data fields that are displayed. The Advanced display shows a larger, configurable data field  
with a white background. The Data Field Setup screen allows you to specify the type of data displayed and  
either a Narrow (Small) or Wide (Larger) size format for each data field.  
Sonar Page With  
Advanced Data Fields  
The following selections require the proper NMEA data (see pgs. 5-6) in order to display information in  
a data field: Bearing, Compass, Course, Distance to Next, Off Course, Pointer, Position, Speed, Time Of Day,  
Track, Turn, and VMG. NMEA Input/Output must also be enabled to receive this data (see pg. 20).  
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To toggle the data field display:  
Unit Operation  
1. Use the ARROW keys to highlight the ‘Advanced Data Fields’ field and press ENTER.  
2. Select ‘On’ or ‘Off’ and press ENTER.  
To access the Advanced data setup:  
Main Menu Options  
1. Use the ARROW keys to highlight ‘Configure Advanced Data Fields’ and press ENTER.  
You may either directly edit an existing field on the left or add a new data field from the list on the right.  
Highlighted items on the right are displayed with a black background and the associated field on the left is  
outlined with a moving dotted line.  
To modify or add a data field:  
1. Using the ARROW keys, press LEFT to modify an existing field or RIGHT to add a new one, then UP or  
DOWN to highlight the desired item. Press ENTER and the available options will appear on the right.  
2. Select an option from the list on the right and press ENTER. You may choose to display a ‘Wide’ or  
‘Narrow’ sized format (some data fields are only available in ‘Wide’ format and this option will be grayed  
out), arrange the display order with ‘Move Up’ or ‘Move Down’ (Narrow data fields always arrange  
below Wide data fields), ‘Remove’ or ‘Replace’ the data field. For ‘Replace’, choose a replacement item  
from the list and press ENTER.  
Data Field Setup screen  
Modifying a Data Field  
3. Highlight ‘OK’ and press ENTER to save changes.  
Temp (Temperature) Tab  
Displays the water temperature log (if equipped with a temperature transducer/sensor). The graph reads  
from right to left, so that the most recent temperature measured is displayed on the far right side of the  
graph. The dotted lines within the graph indicate intervals in the temperature scale and the duration of time.  
The following settings are available:  
•
•
•
Log and Graph Scale — sets the temperature range (in degrees) for displaying the log. Select  
‘Auto’ to have the unit determine the best range, or select a span of 2, 4, 6, 8 or 10 degrees.  
Reset (Scale) — resets the scale range for the temperature graph. Useful when the scale spans a  
large range due to extreme temperature changes. Only shows if Log and Graph Scale is set to ‘Auto’.  
Main Menu - Temp Tab  
Log Duration — sets how fast or slow the temperature log scrolls; the shorter the time duration,  
the faster the temperature log scroll. Select a duration from 1 minute to 2.5 hours.  
18  
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Alarms Tab  
Unit Operation  
Contains settings for the unit’s alarms. (For a list of alarms and unit messages, see page 28.) The Alarms  
Tab is divided into two submenu tabs: Sonar alarms and System alarms.  
Sonar alarms:  
Main Menu Options  
•
•
Fish — sets alarm/icon to sound/display when unit detects a fish of the specified symbol size.  
Shallow Water/Deep Water — set alarms to sound when you enter an area of specified depth that  
is too shallow and/or too deep.  
•
•
Drift — sets an alarm to sound when you’ve exceeded a specified drift depth range. For example, if  
the value is set to 5 ft. and the current depth is 20 ft., the alarm will sound if the unit detects a depth  
greater than 25 ft. or shallower than 15 ft.  
Water Temperature — sets an alarm to sound when the transducer reports a temperature either  
above, below, inside or outside the specified values.  
System alarms:  
Main Menu -  
Alarms/Sonar Tab  
•
•
Battery — sets an alarm to sound when the battery is reaching a critical state of discharge.  
Timer — allows you to choose between a Count Dn (Down) or Count Up timer. You may specify a  
duration for the Count Dn (Down), Stop, or Reset the timer.  
To set an alarm:  
1. Use the ARROW keys to highlight desired submenu tab of the Alarms Tab.  
2. Highlight the field below the alarm name you wish to activate and press ENTER.  
3. Change the mode to the desired setting and press ENTER.  
4. Highlight the next field to the right and press ENTER, then enter the desired settings and press  
ENTER to finish.  
5. If you want the alarm to display and beep until acknowledged, highlight the ‘Persist’ box and press  
ENTER to place a check mark in the box.  
Main Menu -  
Alarms/System Tab  
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System Tab  
Unit Operation  
Controls various system and interface settings. The following settings are available:  
•
Beeper — controls audible beep. Select from ‘Off’, ‘Alarms Only’ (sounds for alarms/messages), or  
‘Key and Alarm’ (sounds for key presses and alarms/messages).  
Main Menu Options  
•
Display Mode — select ‘Fishfinder’ to display the scrolling sonar image on the Sonar Page, or select  
‘Depth Sounder’ to show only numeric data for Depth, Water Temp, and Water Speed.  
•
•
Language — select from various languages for the unit’s on-screen display.  
Simulator — lets you simulate unit operation using a Depth Only, Depth/Temp, Depth/Speed, or  
Depth/Temp/Speed transducer. If prompted, choose ‘No’ to the retail demonstration mode for normal  
consumer simulator use. If the unit does not detect a transducer, it will automatically enter Simulator  
Mode. While in Simulator mode, a ‘Running Simulator’ message appears after 2 minutes of inactivity.  
•
NMEA Input/Output — controls the input/output of NMEA 0183 version 2.3 data to/from the unit.  
This setting must be ‘On’ in order to receive GPS navigational data and send Sonar NMEA data. See  
pages 5-6 for details on available NMEA sentences.  
•
•
•
Factory Settings — restores all settings to the original factory default values for the entire unit.  
Software Version — displays the unit’s software version and electronic serial number.  
Main Menu - System Tab  
Reset Odometer — this will only appear if you are using a speed-capable transducer/sensor. Resets the  
odometer field back to zero. See “Configuring Advanced Data Fields” on p. 17 for more information.  
Units Tab  
Defines units of measure. The following settings are available:  
•
•
•
Depth — select units of measure for depth in Feet (ft), Fathoms (fa), or Meters (m).  
Temperature — select units of measure for temperature in Fahrenheit (°F) or Celsius (°C).  
Distance and Speed — select units of measure for distance and speed readouts in ‘Nautical’ (nm/ft,  
kt), ‘Nautical’ (nm/m, kt), ‘Statute’ (mi, mh) or ‘Metric’ (km, kh) terms.  
•
Position Format — changes the coordinate system in which a position reading is displayed.  
The default format is latitude and longitude in degrees, minutes, and thousandths of a minute  
(hddd°mm.mmm’). The following additional formats are available: Latitude/longitude in decimal  
degrees (hddd.ddddd°) and Latitude/longitude in degrees, minutes, and seconds (hddd°mm’ss.s”).  
Main Menu - Units Tab  
20  
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•
Heading — select the reference used in calculating heading information for the the following  
Advanced data fields: Bearing, Compass, Course, and Track (see pg. 17-18). ‘True’ will display data  
with reference to True North. ‘Magnetic’ will display data with reference to Magnetic North using the  
magnetic variation value received in the RMC NMEA sentence (see pgs. 5-6).  
Unit Operation  
Main Menu Options  
Sonar Tab  
Allows you to set up initial settings and calibrations. The following settings are available:  
•
Water Type — since sound waves travel through ‘Fresh’ and ‘Salt’ water at different rates, it is  
necessary to select the ‘Water Type’ to ensure accurate readings on the unit.  
•
Depth Number — controls the efficiency of the digital depth update rate. ‘Fast Sonar Update’  
updates quicker and is recommended for low-noise, deeper water (>50 ft.). ‘Auto’ is best for shallow  
water or high noise areas, has a slower screen update, and is best used if you travel a wide variety of  
depths. If the unit is unable to track the bottom for any reason, the digits in the depth window flash  
on and off to alert you.  
•
•
Automatic Scroll Speed Limit — automatically adjusts the Scroll rate (see pg. 14) to the speed  
of your vessel (if equipped with a speed sensor or receiving GPS NMEA input). Entering your maximum  
cruising speed will produce a 100% scroll rate when you reach that speed. One half of that speed  
will produce a 50% scroll rate, etc.  
Main Menu - Sonar Tab  
Keel Offset — allows you to offset the surface reading for the depth of a keel in order to measure  
depth from the bottom of your keel instead of from the transducer’s location. Enter a positive  
number to offset for a keel. It is also possible to enter a negative number to compensate for a large  
vessel that may draw several feet of water. The ‘Keel Offset’ will be reflected in the depth reading.  
Transducer at Surface  
Enter (+) positive Keel Offset  
number to show depth  
from bottom of keel  
•
•
Transducer Type — does not appear in Simulator Mode. Allows you to specify what type of trans-  
ducer you are using. ‘User Defined’ is reserved for future use. Do not use unless instructed.  
Calibrate Water Speed — this will only appear if you are using a speed-capable transducer/sensor.  
Calibration is required to ensure that the Water Speed displayed on your unit is accurate. The unit  
automatically uses GPS ground speed (if available via NMEA input) for comparison on the calibra-  
tion. If a GPS ground speed is not available, use either your boat’s speedometer reading (not always  
Transducer at Bottom of Keel  
Enter (-) negative Keel Offset number to  
show depth from surface  
21  
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accurate) or a stopwatch to determine your speed over a certain distance (distance / time = speed). It  
is recommended that the calibration take place in water having little or no current.  
Unit Operation  
To calibrate the water speed:  
1. Use the ARROW keys to highlight ‘Calibrate Water Speed’ and press ENTER.  
Main Menu Options  
2. Bring the boat to a cruising speed. Both the top GPS ground speed and uncalibrated water speed will  
be shown at the bottom of the calibration window. Note your top speed, then stop the boat and press  
ENTER.  
3. By default, the top speed will automatically show in the ‘What was your top water speed?’ field. If a  
ground speed is not available, the top uncalibrated water speed is used instead. If the new speed is  
correct, highlight ‘OK’ and press ENTER. To manually enter a calibration, press ENTER on the speed  
field, enter a new speed and press ENTER.  
If the boat is not moving fast enough or the speed sensor is not registering a speed, a  
“Boat Is Not Moving Fast Enough To Calibrate” message is displayed at the bottom of the  
,
screen. Check that the speed sensor wheel is moving or safely increase boat speed. If there  
is a problem with the speed sensor/unit or if a speed senor is not installed, a “Water Speed  
Sensor Is Not Working” message is displayed at the bottom of the display. Check connec-  
tions of speed sensor cables.  
Calibrating the Speed Sensor  
Time Tab  
Displays the current time and date, allows you to adjust the 12 or 24 hour time format, select a time  
zone and adjust for daylight saving to show correct local time. The time will only display if you are receiving  
valid NMEA input from a GPS unit (see pgs. 5-6) or in simulator mode. The following settings are available:  
•
•
Time Format — choose from 12 or 24 hour (military) time format.  
Time Zone — choose your correct time zone to show correct local time or enter a UTC (also called  
Greenwich Time) Offset. The UTC offset is how many hours you are ahead or behind the time line.  
•
•
Daylight Saving Time — choose from ‘Auto’, ‘On’, or ‘Off’ to adjust for daylight saving.  
Current Time and Current Date — display current time and date. Fields will be blank if not  
receiving a time from an attached GPS. It is not possible to edit these fields.  
Main Menu - Time Tab  
22  
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Understanding Sonar  
On the Water  
If you are unfamiliar with basic sonar, or need help determining what is displayed on the graph, this  
section may be for you. This section is intended to help the novice user gain some understanding of how the  
Fishfinder 250/250C operates and how it can help improve their fishing productivity.  
Understanding Sonar  
To understand what the unit is displaying, it is important to have a general knowledge of how the unit  
works and how it determines what to display. Basically, the unit operates by transmitting sound waves  
toward the bottom of a lake, stream, or seabed in a cone-shaped pattern. When a transmitted soundwave  
strikes an underwater object such as the bottom, a piece of structure, or a fish, sound is reflected back to the  
transducer. The transducer collects the reflected sound waves and sends the data to the unit to be processed  
and displayed on the graph. The underwater data is displayed on the graph in the order that it is returned:  
first returned—first on the graph. The diagram below demonstrates this by showing an underwater scene  
as it would be displayed on the graph. Generally speaking, if the only thing between the transducer and the  
bottom is water, the first strong return will come from the bottom directly below the transducer. The first  
strong return sets the bottom level. Weaker secondary returns provide the detailed data. The Fishfinder 250  
displays sonar returns as shades of gray; stronger returns are darker, and weaker returns are lighter. On the  
Fishfinder 250C, sonar returns are displayed as red (strongest), then orange (strong), yellow (medium),  
green (weaker) and blue (weakest).  
The following pages will show how this data can help you to improve your fishing.  
1
2
3
2
1
3
This fish is currently in a dead zone and is not  
detected by the sonar. The fish is in the coverage  
area of the transducer, but remember– the first  
strong return sets the bottom level. The fish will  
eventually be detected when the first strong return  
sets the bottom level below the fish.  
23  
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Transducer Coverage  
On the Water  
The area covered by the transmitted sound waves is determined by the cone angle of the transducer  
and the water depth. Cone angles may vary between different types of transducers. For example, a 50kHz  
frequency may provide a “wide” 40° cone angle, with a coverage width that is approximately 2/3 of the water  
depth. As shown in the diagram on the left, the 40° cone angle (50kHz frequency) approximately covers the  
area of a 20 foot diameter circle at a 30 foot depth. A 200kHz frequency may provide a “narrow” 10° cone  
angle, with a coverage width that is approximately 2/10 of the water depth. As shown, the 10° cone angle  
(200kHz frequency) approximately covers the area of a 6 foot diameter circle at a 30 foot depth.  
Transducer Coverage  
When using the Fishfinder 250/250C in ‘Dual’ frequency mode, the unit alternately transmits 50kHz  
and 200kHz signals and combines the information. The ‘Dual’ frequency capability of the Fishfinder 250/  
250C allows the user to have a large coverage area and still retain good bottom resolution. When in ‘Dual’  
frequency mode the unit uses the narrow cone angle (200kHz) to display detailed bottom information,  
keeping “Dead Zones” to a minimum, and the wide cone angle (50kHz) for the large coverage area.  
Fish returns from the wide and narrow beams appear differently on the display. The wide beam tends to  
show longer fish returns than the narrow beam, as shown in the diagram below.  
200kHz - 10˚ Cone Angle  
72" coverage at 30'  
50kHz - 40˚ Cone Angle  
20' coverage at 30'  
Narrow Cone Angle  
Wide Cone Angle  
24  
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Understanding the Graph  
On the Water  
It is important to understand that the unit does not display a 3-D representation of the underwater  
environment. The unit can display multiple items at the same time, but cannot determine where each return  
originated – only when it was received.  
Understanding the Graph  
Examples 1 and 2 provide a look at the underwater world from a top view, and illustrate how these  
views would be displayed on the graph. On both graphs it appears the fish and tree are side by side as  
shown in Example 1. However, when we look at Example 2, we see that the fish can be several feet from the  
tree. It is important to remember that the Fishfinder cannot determine where in the coverage area the tree or  
fish are, only that the returns were received at the indicated depths in the same time frame.  
)
Enlarged  
Transducer  
View  
Enlarged  
Transducer  
View  
Remember that the Fishfinder displays a 2-D picture of  
the underwater environment. The fish and tree could be  
located anywhere in the coverage area at that time.  
Branches  
Fish  
Branches  
Fish  
Example 1.  
Example 2.  
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25  
Whiteline  
On the Water  
The Fishfinder 250/250C can help you to determine if the bottom is hard or soft. When the sonar  
soundwaves are reflected back by the bottom, a hard bottom returns a stronger signal than a soft bottom.  
A thin whiteline indicates a softer bottom while a thick whiteline indicates a harder bottom. Normally, the  
Fishfinder 250 uses a black line and the Fishfinder 250C uses a red line to show the point where water  
meets the bottom. This line follows the bottom contour, along with any significant objects lying on the  
bottom. The unit uses the whiteline  
Whiteline and Thermoclines  
function to make this bottom layer  
information easier to distinguish.  
)
Whiteline can also help you to determine the type of bottom struc-  
ture that is displayed on the graph. By determining the hardness  
of the structure, you can make a better informed decision on the  
type of structure.  
With the Fishfinder 250/250C,  
whiteline helps accentuate where  
strong signals are located, which  
make bottom type determination  
easier. The example to the right  
shows the bottom return with and  
without the whiteline activated.  
See page 14 for more information.  
Whiteline Turned Off  
Whiteline  
Soft Bottom  
Hard Bottom  
Thermoclines  
One of the unique features offered by Garmin is  
®
®
See-Thru technology. See-Thru technology allows the  
Fishfinder 250/250C to “see” through thermoclines and  
helps locate fish where they live -- and fish love thermo-  
clines. A rough definition of a thermocline is a break in  
water where the water temperature changes faster than in  
the water above it. Thermoclines give weak returns and are  
shown as the weakest colors/shades (see pg. 11).  
Thermocline  
Structure is hard—  
probably a rock or stump  
Structure is soft—  
probably a mud pile  
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Physical Specifications  
Appendix A  
Size:  
6.1" W x 4.9" H x 2.9" D (15.5 cm x 12.5 cm x 7.4 cm)  
Weight:  
Display:  
1.1 lbs. (0.5 kg)  
(Fishfinder 250) 4.5" diagonal (11.4 cm), 3.2” W x 32” H (8.1 cm x 8.1 cm) high-contrast  
10-level grayscale FSTN display with adjustable brightness (320 x 320 pixels)  
Specifications, Cleaning and  
Storage  
(Fishfinder 250C) 4.5" diagonal (11.4 cm), 3.2” W x 3.2” H (8.1 cm x 8.1 cm)  
high-contrast, 16-color CSTN display with adjustable brightness (320 x 320 pixels)  
Case:  
Fully gasketed, high-impact plastic alloy, waterproof to IEC 60529 IPX7 standards  
5°F to 130°F (-15°C to 55°C)  
Temp. Range:  
Power  
Source:  
Usage:  
Fuse:  
10-35 volts DC  
17 watts max. at 10 volts DC; 15 watts at 13.8 volts DC nominal  
AGC/3AG - 2.0 Amp  
Sonar  
Power:  
Dual frequency: 500 watts (RMS); 4000 watts (peak to peak)  
Single frequency: 400 watts (RMS); 3200 watts (peak to peak)  
Frequency:  
Depth:  
50/200 kHz  
1500 foot max depth (Depth capacity is dependent on water salinity, bottom type and other water  
conditions.)  
Cleaning and Storage  
The Fishfinder 250/250C is constructed of high quality materials and does not require user maintenance  
other than cleaning. Clean the unit using a cloth dampened with a mild detergent solution and then wipe dry.  
Avoid chemical cleaners and solvents that may damage plastic components.  
Do not store the Fishfinder 250/250C where prolonged exposure to temperature extremes may occur (such as  
in the trunk of a car) as permanent damage may result. Unit settings will be retained in the unit’s memory without  
the need for external power.  
27  
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Battery Alarm — Battery voltage has fallen below the value entered in the Battery Alarm setup.  
Battery Voltage High— Input voltage too high, unit will shut off. You must lower input voltage.  
Appendix B  
Boat is not Moving Fast Enough to Calibrate — Boat is not moving fast enough for the speed wheel to  
provide a valid speed.  
Messages and Alarms  
Can’t Send Waypoint — Unit was unable to transmit the waypoint via the NMEA WPL sentence. Check  
wiring.  
The Fishfinder 250/250C uses an on-screen  
pop-up message system to alert you to unit  
operating characteristics. Press the ENTER key to  
acknowledge the message.  
Can’t Read Voltages That High Limited To Top Of Range — Voltage value in the Battery Alarm setup is  
higher than the unit can read.  
Can’t Read Voltages That Low Limited To Bottom Of Range — Voltage value in the Battery Alarm  
setup is lower than the voltage where the unit automatically turns off.  
Deep Water Alarm — Deep Water Alarm depth has been reached.  
Drift Alarm — Depth has changed by the amount entered in the Drift Alarm setup.  
Fish Alarm — Displays icon and sounds beep (if enabled) when a fish is detected. (This alarm does not  
display a message banner.)  
Running Simulator — Unit is in Simulator Mode. This message will reappear after 2 minutes of inactivity.  
(If the unit does not detect a transducer attached, it will automatically enter Simulator Mode.)  
Shallow Water Alarm — Shallow Water Alarm depth has been reached.  
Sonar Failed Unit Needs Repair — Internal problem with unit. Contact your dealer or Garmin Product  
Support to have the unit serviced.  
Timer Alarm — Timer Alarm value has counted down to 00:00:00.  
Transducer Disconnected Sonar Turned Off — No transducer attached, bad cable/transducer or trans-  
ducer cable was disconnected. If the transducer cable is removed while the unit is on, reconnect and cycle  
power.  
Water Speed Sensor is not Working — Speed sensor is not detected. Check Connections.  
Water Temperature Alarm — Water Temperature Alarm setting has reached value above, below, inside, or  
outside of specified value(s).  
28  
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Date 22  
A
Appendix C  
Daylight Savings Time 22  
Deep Water Alarm 19  
Defaults 14, 20  
Depth 11-12, 15-17, 20  
Depth Line 14  
Depth Number 17, 21  
Depth Units 20  
Display Mode 20  
Distance Units 20  
Drift Alarm 19  
Accessories iv-v  
ADJ/MENU Key 10  
Adjustment Menu 12  
Adjustment Menu Options 12  
Advanced Data Fields 17  
Advanced Display 17  
Alarms 19, 28  
Alarms Tab 19  
ARROW Keys 10  
Automatic Scroll Speed 21  
Index  
I
Installation 1-9  
Interfacing 5-6  
K
E
Keel Offset 21  
B
Keypad Usage 10  
ENTER Key 10  
Background Color 17  
Backlight 10  
L
F
Language Selection 20  
Log and Graph Scale 18  
Log Duration 18  
Basic display 17  
Battery Alarm 19  
Beeper 20  
Bottom Lock 13  
Bottom Split 13  
Factory Settings 20  
Fish Alarm 19  
Fish Symbols 11, 16  
Flasher 11, 17  
Frequency 14  
M
Main Menu 16-22  
Messages 28  
Fuse 5, 27  
C
G
Calibrate Water Speed 21-22  
Cleaning 27  
Color, Background 17  
Color Bar 13, 17  
Contrast 10  
Gain 13  
Graph 25  
Graph Tab 16  
N
NMEA 5-6, 15, 20-22  
NMEA Setup 20  
Noise Reject 14  
Custom Range 16  
H
D
Number Size 17  
Heading 21  
Data Fields 11, 17  
29  
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Size Split 14  
U
Appendix C  
Software License Agreement iii  
Software Version 20  
Sonar, Understanding 23-26  
Sonar Page 11  
Understanding Sonar 23-26  
Understanding the Graph 25  
Underwater Waypoints 15  
Units Tab 20  
Index  
Span 13  
P
Specifications 27  
Speed Units 20  
V
Packing List iv  
Pointer 10, 12, 15  
Position Format 20  
POWER/BACKLIGHT key 9-10  
Power Up 9  
View 13  
Split Screen 13-14  
Storage 27  
System Tab 20  
W
Warranty ii  
T
Preface i  
Water Speed 17, 21  
Water Temperature 17, 26  
Water Temperature Alarm 19  
Water Type 21  
Waypoints 15  
Whiteline 14, 26  
Wiring 5, 6  
Table of Contents vi  
Target Level 13  
R
Range 12  
Temperature 17-18  
Temperature Graph 17  
Temperature Tab 18  
Temperature Units 20  
Testing the Installation 9  
Thermoclines 26  
Time 22  
Registration i  
Reset Odometer 20  
Reset Scale 18  
S
Z
Scale 16  
Zoom 11-13  
Timer 19  
Scroll 14-15  
Time Duration 18  
Time Format 22  
Time Tab 22  
Time Zone 22  
Tools Tab 17  
Scroll Speed 21  
Serial Number ii  
Setting an Alarm 19  
Shallow Water Alarm 19  
Simulator 20  
Transducer v, 7-9, 14, 23-24  
Transducer Type 21  
30  
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For the latest free software updates (excluding map data) throughout the  
life of your Garmin products, visit the Garmin web site at www.garmin.com.  
© Copyright 2004 Garmin Ltd. or its subsidiaries  
Garmin International, Inc.  
1200 East 151st Street, Olathe, Kansas 66062, U.S.A.  
Garmin (Europe) Ltd.  
Unit 5, The Quadrangle, Abbey Park Industrial Estate, Romsey, SO51 9DL, U.K.  
Garmin Corporation  
No. 68, Jangshu 2nd Road, Shijr, Taipei County, Taiwan  
www.garmin.com  
Part Number 190-00328-00 Rev. A  
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