GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

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

DTC Descriptor

DTC B0000 5A: Vehicle Speed Information Circuit Plausibility Failure

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Vehicle Speed Signal

B0000 5A

B0000 5A

B0000 5A

B0000 5A

Circuit/System Description

The radio receives a vehicle speed signal from the electronic brake control module (EBCM) in order to correlate actual vehicle speed to the movement of the vehicle calculated by the navigation system and reported serial data.

Conditions for Running the DTC

    â€¢ Radio ON.
    â€¢ Battery voltage must be between 9-16 volts.

Conditions for Setting the DTC

    â€¢ Vehicle speed from serial data is more than 5 km/h (3 mph) and vehicle speed pulse from the EBCM is 0 km/h (0 mph).
    â€¢ Vehicle speed calculated from the navigation processing software is more than 36 km/h (22 mph) and vehicle speed pulse from the EBCM is 0 km/h (0 mph) for 10 seconds continuously.

Action Taken When the DTC Sets

    â€¢ Turn by turn route navigation may be inoperative.
    â€¢ Vehicle indicated location may be inaccurate.

Conditions for Clearing the DTC

    â€¢ The condition responsible for setting the DTC no longer exists.
    â€¢ A history DTC clears after 100 malfunction-free ignition cycles.

Reference Information

Schematic Reference

Radio/Navigation System Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Navigation System Description and Operation

Electrical Information Reference

    â€¢  Circuit Testing
    â€¢  Connector Repairs
    â€¢  Testing for Intermittent Conditions and Poor Connections
    â€¢  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Testing

Important:  Diagnose any antilock brake system (ABS) related DTCs before performing this diagnostic.

  1. Ignition OFF, disconnect the X4 harness connector at the radio.
  2. Ignition ON, operate the vehicle drive wheels at 5 mph. Test for 3-7 Hertz between the VSS circuit terminal 5 and ground.
  3. ⇒If not within the specified range, test the VSS circuit for an open, high resistance, short to ground or short to voltage. If the circuit tests normal replace the EBCM.
  4. If the circuit tests normal, replace the radio.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for radio or EBCM replacement, setup, and programming