GM Service Manual Online
For 1990-2009 cars only

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.

DTC Descriptors

DTC B2462 02: Global Positioning System (GPS) Short to Ground

DTC B2462 04: Global Positioning System (GPS) Open Circuit

Circuit Description

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

Conditions for Running the DTC

    • Radio ON
    • Battery voltage between 9-16 volts
    • The navigation radio tests the GPS antenna every 10 seconds

Conditions for Setting the DTC

B2462 02

The navigation radio detects a short to ground in the GPS antenna signal circuit.

B2462 04

The navigation radio detects an open/high resistance in the GPS antenna signal circuit.

Actions Taken When the DTC Sets

    • The radio uses the last reported position and the vehicle speed signal to calculate the vehicle position.
    • Route guidance may be inaccurate.
    • Turn by turn navigation may be inaccurate or inoperative.

Conditions for Clearing the DTC

    • The condition responsible for setting the DTC no longer exists.
    • A history DTC will clear once 50 consecutive malfunction-free ignition cycles have occurred.

Reference Information

Schematic Reference

Radio/Navigation System Schematics

Connector End View Reference

Entertainment/Communication Connector End Views

Electrical Information Reference

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

Circuit/System Testing

Note: 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 coax cable connection center conductor at the radio and ground.
  3. If not within the specified range, replace the radio.
  4. If all circuits test normal, replace the GPS antenna.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

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