Garmin GPS 40 Manual

The Garmin GPS 40 is a rugged, handheld GPS receiver designed for outdoor navigation. It features a 12-channel parallel receiver for fast satellite acquisition, a high-contrast LCD display, waterproof construction (IPX7), waypoint and route storage, track log recording, and NMEA 0183 output for interfacing with other marine electronics. Below are key sections for safety, features, installation, setup, operation, and troubleshooting.

Features at a Glance

Key components: 12-channel GPS receiver, LCD display with backlight, waterproof case, external antenna port, serial data interface, and four AA battery compartment.

Feature	Description
12-channel receiver	Fast acquisition and tracking of GPS satellites
LCD display	High-contrast, 4-line display with adjustable backlight
Waterproof rating	IPX7 (submersible to 1 meter for 30 minutes)
Waypoint storage	Up to 500 user-defined waypoints
Route storage	Up to 20 reversible routes with 30 waypoints each
Track log	Automatic track recording with 10 saved tracks
NMEA 0183 output	Interface with autopilots, chartplotters, or PCs
External antenna port	For connection to an external GPS antenna
Battery life	Approximately 24 hours on AA alkaline batteries
Position format	Selectable (Lat/Lon, UTM, MGRS, etc.)

Installation & Power

Unpack and inspect contents. Install batteries or connect to external power.

1. Install batteries: Open battery compartment, insert four AA batteries (alkaline or NiMH).
2. External power: Use optional DC power cable (10-40 VDC) for marine or vehicle use.
3. External antenna: Connect optional active GPS antenna to external antenna port if needed.
4. Data cable: Connect optional PC interface cable to serial port for data transfer.

WARNING! Use only recommended batteries. Ensure battery polarity is correct to avoid damage.

First-Time Setup

Power on unit; acquire satellites; configure initial settings.

1. Acquire satellites: Turn unit on outdoors with clear sky view. Allow several minutes for first fix.
2. Set language: In SETUP menu, select language (default ENGLISH).
3. Set position format: Choose preferred coordinate system (e.g., hddd°mm.mmm').
4. Set map datum: Select datum matching your charts (default WGS 84).
5. Set time format: Choose 12-hour or 24-hour format and time zone.

CAUTION! Initial satellite acquisition requires clear view of sky. Avoid obstructions.

Specifications

• Receiver: 12-channel parallel, GPS only (no GLONASS).
• Update Rate: 1 second continuous.
• Accuracy: Position: <15 meters RMS, Velocity: 0.1 knot RMS.
• Acquisition Time: Hot start: ~15 seconds, Warm start: ~45 seconds, Cold start: ~2 minutes.
• Display: 4-line x 16-character LCD with LED backlight.
• Interface: NMEA 0183 v2.0, GARMIN proprietary.
• Power: 4 AA batteries (alkaline or NiMH) or external 10-40 VDC.
• Waterproof: IPX7 standard.
• Operating Temp: -15°C to 70°C (5°F to 158°F).
• Dimensions: 15.5 x 6.4 x 3.3 cm (6.1" x 2.5" x 1.3").
• Weight: 255 g (9 oz) with batteries.

Controls and Display

Access functions via front panel buttons. Display shows navigation data pages.

Buttons: POWER, PAGE, ENTER, GOTO, MARK, UP/DOWN arrows.

Display Pages: Satellite Status, Position, Compass, Highway, Map, Menu.

Satellite Page: Shows satellite sky view, signal strength, and fix status (2D/3D).

Position Page: Shows coordinates, altitude, speed, heading, and time.

Compass Page: Shows bearing to destination, distance, and steering guidance.

Menu Options: Waypoints, Routes, Tracks, Setup, System.

Basic Navigation

Navigate to a waypoint or follow a route.

1. Mark a waypoint: Press and hold MARK at current location. Edit name/symbol if desired.
2. Go to a waypoint: Press GOTO, select waypoint from list, press ENTER.
3. Follow a route: Create route in ROUTE menu, then activate it for navigation.
4. Steering: Use Compass or Highway page for guidance to destination.
5. Track navigation: Follow a saved track back (TRACK BACK function).

Tip: For best accuracy, ensure 3D fix (at least 4 satellites) before navigating.

Advanced Functions

Utilize waypoint management, routes, tracks, and setup options.

1. Waypoint projection: Create waypoint at a bearing/distance from current position.
2. Route creation: Build route by selecting existing waypoints in sequence.
3. Track log: Record track automatically; save up to 10 tracks; clear track log.
4. Setup options: Adjust contrast, backlight timeout, beeper, coordinate system, datum, units.
5. Simulator mode: Practice navigation indoors (enable in SYSTEM menu).

WARNING! Saved data (waypoints, routes, tracks) may be lost if batteries are removed for extended period.

NMEA Interface

Connect to external devices for data output/input.

1. Connect cable: Use optional data cable to connect to device serial port.
2. Set NMEA output: In INTERFACE menu, set format to NMEA 0183.
3. Select sentences: Choose which NMEA sentences to output (e.g., GGA, RMC).
4. Baud rate: Set to match connected device (default 4800 bps).

CAUTION! Ensure correct wiring (TX, RX, GND) to avoid damage to equipment.

Care & Maintenance

Clean with fresh water after saltwater use. Store in cool, dry place.

Cleaning: Use soft, damp cloth. Do not use solvents or abrasive cleaners.

Battery: Replace batteries when low battery indicator appears. Remove batteries for long-term storage.

CAUTION! Do not open unit; no user-serviceable parts inside. Refer servicing to qualified personnel.

Regulatory Information

FCC Part 15: Class B digital device; complies with interference limits. This device complies with part 15 of the FCC Rules. Operation is subject to the condition that this device does not cause harmful interference. Copyright © Garmin Ltd. or its subsidiaries. Garmin and the Garmin logo are trademarks of Garmin Ltd. or its subsidiaries. For support, visit www.garmin.com/support or contact Garmin Product Support.

Troubleshooting

Symptom	Possible Cause	Corrective Action
No power	Dead batteries	Replace with fresh AA batteries; check polarity.
No satellite fix	Obstructed view	Move to open area with clear sky view; wait several minutes.
Poor accuracy	Multipath or weak signals	Ensure clear view; avoid buildings/canyons; check satellite page for strong signals.
Display blank/faded	Contrast setting	Adjust contrast in SETUP menu; replace batteries if low.
Waypoint not found	Wrong datum/format	Ensure coordinate format and map datum match source of waypoint.
NMEA not working	Cable/baud rate	Check cable connections; verify baud rate matches receiving device.

Reset: Press and hold PAGE + POWER while turning on to reset to factory defaults (erases user data).

Service: Contact Garmin Product Support or authorized service center.