B2483

DTC B2483 or B2484

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview)provides an overview of each diagnostic category.

DTC Descriptors
DTC B2483 00
- GPS Sensor Circuit Low

DTC B2484 00
- GPS Sensor Circuit Open

Circuit/System Description

The navigation antenna is connected to the vehicle communication interface module (VCIM) with a RG-174 coax cable. The VCIM polls the data from the navigation antenna once every second.

Conditions for Running the DTC

* The ignition must be in the RUN or ACC position.
* The system voltage is at least 9.5 volts and no more than 15.5 volts.
* All the above conditions are present for greater than 1 second.

Conditions for Setting the DTC

* The VCIM does not detect a navigation signal.
* The above conditions are present for greater than 1 second.

Action Taken When the DTC Sets

* The OnStar(R) Call Center cannot locate the vehicle.
* The OnStar(R) status LED turns red.

Conditions for Clearing the DTC

* The VCIM detects the presence of a navigation antenna.
* A history DTC clears after 50 malfunction-free ignition cycles.
* The VCIM receives the clear DTC command from the scan tool.

Reference Information
Schematic Reference

OnStar Schematics (OnStar Schematics)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

OnStar Description and Operation (OnStar Description and Operation)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning)for scan tool information

Circuit/System Verification

Observe that the cellular antenna and cellular antenna coupling assembly are not damaged.

If it is damaged, replace the cellular antenna.

1. Disconnect the navigation antenna coax connector from the navigation antenna and VCIM.
2. Test for infinite resistance between the center conductor of the coax to the metal outer shield.

• If not specified value, replace the navigation antenna coax.

3. Test for less than 1 ohm resistance of navigation antenna coax center conductor from end to end.

• If not specified value, replace the navigation antenna coax.

4. If cellular antenna coax tests normal, test or replace the VCIM.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Cellular Communications/Digital Radio Antenna Replacement (Cellular Communications/Digital Radio Antenna Replacement)
* Control Module References (Programming and Relearning)for VCIM replacement, setup, and programming