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B2462




DTC B2462

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.

* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC B2462 01
- Global Positioning System Short to Battery

DTC B2462 02
- Global Positioning System Short to Ground

DTC B2462 04
- Global Positioning System Open

Circuit/System Description

The navigation antenna is connected to the telematics communication interface control module and the radio through the navigation signal splitter. The navigation signal splitter distributes the navigation signal to both the telematics communication interface control module and the navigation radio. The telematics communication interface control module supplies 5 V through the coax cable to power the internal antenna amplifier through the signal splitter. The radio supplies 5 V through the center conductor of the coax cable to power the splitter.

Conditions for Running the DTC

* Radio On.

* System voltage is greater than 9 V and less than 16 V.

* The navigation radio tests the GPS antenna every 10 seconds.

Conditions for Setting the DTC

B2462 01

The navigation radio detects a short to B+ on the GPS antenna signal circuit.

B2462 02

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

B2462 04

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

Action 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.

Diagnostic Aids

* This DTC can only be retrieved from the radio. The telematics communication interface control module does not set this DTC.

* The radio only monitors the connection between the navigation signal splitter and the radio. The radio cannot detect faults between the signal splitter and the navigation antenna. Faults between the signal splitter and the navigation antenna will result in a loss of GPS signal without setting DTC B2462.

* The navigation antenna requires a clear line of sight to the sky to operate properly. The GPS may have limited, intermittent, or no reception near tall buildings or inside structures.

Reference Information

Schematic Reference

* OnStar Schematics OnStar Schematics

* Radio/Navigation System Schematics Radio/Navigation System Schematics

Connector End View Reference

Component Connector End Views Fuel Pump and Level Sensor Assembly

Description and Operation

* OnStar Description and Operation OnStar

* Radio/Audio System Description and Operation (with Monochrome Display) Radio/Audio System Description and Operation (with Monochrome Display)Radio/Audio System Description and Operation (with Color Display) Radio/Audio System Description and Operation (with Color Display)

Electrical Information Reference

* Circuit Testing Circuit Testing

* Connector Repairs Connector Repairs

* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections

* Wiring Repairs Wiring Repairs

Scan Tool Reference

Control Module References Control Module References for scan tool information

Special Tools

EL-49903EL-49903 - OnStar Antenna Diagnostic Tool Kit

Circuit/System Testing

1. Ignition OFF, disconnect the navigation antenna coax cable connector at the A11 radio. Connect the EL-49903 - GM OnStar antenna diagnostic tool kit to the A11 radio, place the test antenna on the roof of the vehicle.

2. Ignition ON, radio ON, navigation selected.

3. Verify DTC B2462 is not set.

If DTC B2462 is set
Replace the A11 radio.

If DTC B2462 is not set

4. Ignition OFF, disconnect the radio navigation coax cable at the T15 navigation signal splitter.

5. Verify the radio navigation coax cable passes the coax cable component test. Refer to Component Testing.

If the coax cable does not pass the test
Replace the coax cable

If the coax cable passes the test

6. Test or replace the T15 navigation signal splitter.

Component Testing

Caution: Refer to Test Probe Caution Test Probe Caution.

Note: Before testing the coax cable, check the cable exterior for being pinched, cut, damaged, or having loose connections at the components, which can cause reception issues.

To prevent false reading when testing the center coax terminals, use care not to ground the test probe on the outer housing/shield.

Coax Cable Test

1. Ignition OFF, disconnect the coax cable at both components.

2. Test for less than 5 ohms between coax cable center terminal end to end.

If 5 ohms or greater
Replace the coax cable

If less than 5 ohms

3. Test for less than 5 ohms between the coax cable outer shield end to end.

If 5 ohms or greater
Replace the coax cable

If less than 5 ohms

4. Test for infinite resistance between the coax cable center terminal and the coax cable outer shield.

If less than infinite resistance
Replace the coax cable

If infinite resistance

5. All OK

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the repair.

* Navigation Signal Splitter Replacement Service and Repair

* Control Module References Control Module References for radio replacement, programming, and setup.