GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 HUMMER 🢒 2007 🢒 H3 🢒 Driver Information and Entertainment 🢒 Cellular, Entertainment, and Navigation 🢒 No Global Positioning System (GPS) Reception

Diagnostic Instructions
    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Circuit Description

The global positioning system (GPS) antenna is connected to the navigation radio by a shielded coaxial cable. The antenna cable also provides a path for DC current for powering the GPS antenna.

Reference Information

Schematic Reference

Radio/Navigation System Schematics

Connector End View Reference

Entertainment/Communication Connector End Views

Description and Operation

Navigation System Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Scan Tool Data List

Circuit/System Testing

Important: The global positioning system (GPS) requires a clear line of sight to the sky to operate properly. In most cases the GPS will not have reception near tall buildings or inside structures.

  1. Ignition OFF, disconnect the GPS antenna coax cable from the navigation radio.
  2. Ignition ON, test for 4.5-5.5 volts between the radio coax cable connection center conductor and ground.
    3. ⇒If not within the specified range, replace the radio.
  3. If all circuits test normal, replace the GPS antenna.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Electronic Navigation Antenna Replacement
    •  Control Module References for Radio replacement, setup, and programming