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 (GPS) Short to Battery

DTC B2462 02

-
Global Positioning System (GPS) Short to Ground

DTC B2462 04

-
Global Positioning System (GPS) Open Circuit

Circuit Description

The navigation antenna is mounted on the roof of the vehicle and is connected to the navigation radio with a coax cable. The radio supplies 5 V to the antenna to power the internal amplifier thorough the center conductor of the antenna coax cable.

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.

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.

Diagnostic Aids

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

Radio/Navigation System Schematics Radio/Navigation System Schematics

Connector End View Reference

Component Connector End Views Sunshade - Left (DH6)

Description and Operation

Radio/Audio System Description and Operation (with Color Display) Radio/Audio System Description and Operation (with Color Display)Radio/Audio System Description and Operation (with Monochrome Display) Radio/Audio System Description and Operation (with Monochrome 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-49903 EL-49903 - OnStar Antenna Diagnostic Tool Kit

Circuit/System Testing

1. Ignition OFF, disconnect the navigation antenna coax cable from the A11 radio.

2. Connect the EL-49903 to the A11 radio, place the test antenna on the roof of the vehicle.

3. Ignition ON, verify DTC B2462 is not set in the A11 radio.

• If DTC B2462 is set as current, replace the A11 radio.

4. Ignition OFF, reconnect the navigation antenna coax cable at the A11 radio.

5. Disconnect the antenna coax cable from the T4P navigation antenna.

6. Ignition ON, test for 4.5-5.5 V between the coax cable center conductor and the outer shield.

• If not within the specified range, test or replace the coax cable.

7. If all circuits test normal, replace the T4P navigation antenna.

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 both ends of the coax cables center terminals.

• If greater than the specified range, replace the coax cable

3. Test for less than 5 ohms between both ends of the coax cable outer shield.

• If greater than the specified range, replace the coax cable

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

• If less than the specified range, replace the coax cable.

Repair Instructions

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

* Radio Antenna Base Replacement Radio Antenna Base Replacement

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