Garmin GPS 400 Installation Manual

The Garmin GPS 400 series is a panel-mounted aviation GPS navigator providing precise navigation, flight planning, and situational awareness. It features a high-resolution sunlight-readable display, integrated COM and NAV radios (in some models), WAAS-enabled GPS receiver, terrain awareness, traffic information compatibility, and extensive database support. This manual covers essential procedures for safe installation, configuration, and initial setup in certified aircraft.

Overview and Components

Key components: GPS 400 main unit, mounting tray with connectors, remote antenna (GA 56 or compatible), power/data cable harness, external GPS antenna (if required), installation hardware kit, and documentation.

Pre-Installation Requirements

Review aircraft documentation and obtain necessary approvals before beginning.

1. Aircraft Compatibility: Verify unit is approved for your aircraft make/model.
2. Panel Space: Ensure cutout dimensions (typically 6.25" W x 3.25" H) are available.
3. Power Source: Confirm 14V or 28V DC aircraft power supply per unit specifications.
4. Tools Required: Standard aviation toolset, torque wrench, crimping tools, multimeter.

WARNING! Installation must be performed by qualified personnel in accordance with applicable regulations. Disconnect aircraft battery before beginning work.

Mounting and Physical Installation

Secure mounting is critical for safety and performance.

1. Prepare Panel: Mark and cut opening per template provided in kit.
2. Install Mounting Tray: Secure tray to panel using provided hardware and torque to specification.
3. Route Cables: Plan cable routes away from sharp edges, heat sources, and moving controls.
4. Secure Unit: Slide main unit into tray until it clicks and locks into place.

CAUTION! Ensure adequate clearance behind panel for connectors and cables. Do not force unit into tray.

Electrical Connections

• Power Input: 11-33V DC, typically from aircraft avionics bus.
• Ground: Secure connection to aircraft ground point.
• Serial Data Ports: Configure for communication with autopilot, MFD, or other avionics.
• Audio Output: Connect to aircraft audio panel for audible alerts.
• Discrete Inputs/Outputs: For external annunciators or control signals.

Tip: Use shielded wiring for all data lines and maintain proper separation from high-current cables.

Antenna Installation

GPS antenna placement is critical for optimal satellite reception.

Location: Mount on aircraft top skin with clear view of sky, away from prop arc and other antennas. Use provided template for hole drilling.

Connection: Route coaxial cable from antenna to unit, minimizing bends. Secure cable every 18 inches. Connect to ANT port on rear of unit.

Grounding: Ensure antenna base is properly grounded to aircraft skin per instructions.

Initial Configuration & Setup

After power-up, configure basic system settings.

1. Power On: Reconnect aircraft battery and apply power to avionics bus.
2. Initialization: Unit will perform self-test and begin satellite acquisition (may take several minutes).
3. System Setup: Navigate menus to set:
   • Units (NM, KM, etc.)
   • Time Format & Time Zone
   • Navigation Data Fields
   • COM/NAV Frequencies (if equipped)
4. Sensor Configuration: Calibrate internal sensors if required.

Note: First satellite fix may require the unit to be stationary with clear sky view.

Database Loading & Updates

Supports Jeppesen or Garmin navigation databases.

1. Obtain Data Card: Purchase current navigation database subscription.
2. Insert Card: Power off unit, insert data card into appropriate slot (if equipped).
3. Load Database: Power on; unit should recognize and load new database automatically.
4. Verify: Check database effective dates in system information page.

WARNING! Never remove data card while unit is powered on. Ensure database is current for flight operations.

System Integration

Connecting to other aircraft systems.

Refer to interface control document for specific pinouts and protocols.

Post-Installation Testing

Complete functional testing before flight.

1. Ground Test: Verify power-up, display, button/knob operation.
2. GPS Function: Confirm satellite acquisition and position accuracy.
3. Database: Verify navigation data is loaded and current.
4. Communications: Test COM radio functions (if equipped).
5. Integration: Verify data exchange with connected systems (autopilot, MFD).
6. Operational Check: Perform simulated flight planning and navigation.

CAUTION! All testing must be completed with aircraft in a safe, non-operational environment.

Regulatory & Compliance

FAA TSO-C146a (WAAS GPS), TSO-C129 (if applicable). Installation must comply with AC 43.13-1B and aircraft manufacturer's guidelines. STC or Field Approval may be required. This device complies with part 15 of the FCC Rules. For technical support, contact Garmin Aviation Support at 1-800-800-1020 or visit www.garmin.com/aviation.

Troubleshooting

Reset: Consult manual for soft/hard reset procedures if unit becomes unresponsive.

Service: 1-800-800-1020; www.garmin.com/aviation/support