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.

Circuit/System Description

The Vehicle Dynamics Caution indicator is controlled by the instrument cluster via serial data messages from the electronic brake control module (EBCM). When the vehicle stability control system is active for 0.5 seconds, the EBCM commands the instrument cluster to flash the Vehicle Dynamics Caution indicator.

The electronic brake control module (EBCM) sends a serial data message to the instrument panel cluster (IPC) to illuminate the Vehicle Dynamics Caution indicator when the EBCM has disabled the Vehicle Dynamics system (VDC) due to a DTC. The Vehicle Dynamics Caution indicator will also turn ON during the instrument cluster bulb check. When the ignition switch is turned to ON, the Vehicle Dynamics Caution indicator will turn ON for approximately 3 seconds and then turn OFF.

Reference Information

Schematic Reference

Antilock Brake System Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

ABS Description and Operation

Electrical Information Reference

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

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

  1. Turn OFF the ignition for 5 seconds.
  2. Turn ON the ignition, with a scan tool, select instrument panel special functions Display Test. Command the instrument panel lamps ON. Verify the Vehicle Dynamics Caution indicator lamp illuminates for at least 2 seconds and then turns OFF.

Circuit/System Testing

Important: Diagnose all vehicle DTCs before using this diagnostic.

The malfunction must be present during diagnosis in order to prevent unnecessary parts replacement.

  1. Ignition OFF for 5 seconds, ignition ON, observe that the vehicle dynamics caution indicator functions by illuminating for 2 seconds then turns OFF.
  2. If the vehicle dynamics caution indicator does not illuminate, with the scan tool, select instrument panel special functions Display Test. Command the instrument panel lamps ON and OFF. Verify the VDC lamp turns ON and OFF.
    If the VDC warning lamp does not turn OFF, replace the IPC.
    If the VDC warning lamp does turn OFF, replace the EBCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

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

Repair Verification

Ignition OFF for 5 seconds, ignition ON, observe that the vehicle dynamics caution indicator functions by illuminating for 2 seconds then turns OFF. This is the bulb self test that operates upon every ignition key start cycle.