Inspection and Verification

Anti-Lock Control

Inspection and Verification

1. Verify the customer concern.

2. Verify the stoplamps operate correctly by applying and releasing the brake pedal. If the stoplamps do not operate correctly, refer to Lighting and Horns. If the stoplamps operate correctly, proceed to the next step.

3. Verify that the PRNDL operates correctly on the IPC (Instrument Panel Cluster). If the PRNDL does not operate correctly, refer to Instrument Panel, Gauges and Warning Indicators. If the PRNDL operates correctly, proceed to the next step.

4. Visually inspect for obvious signs of mechanical or electrical damage.

Visual Inspection Chart






5. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.

6. NOTE: Make sure to use the latest scan tool software release.
If the cause is not visually evident, connect the scan tool to the Data Link Connector (DLC).


7. NOTE: The Vehicle Communication Module (VCM) LED prove-out confirms power and ground from the DLC (Data Link Connector) are provided to the VCM (Vehicle Communication Module).
If the scan tool does not communicate with the VCM (Vehicle Communication Module) :

- check the VCM (Vehicle Communication Module) connection to the vehicle.

- check the scan tool connection to the VCM (Vehicle Communication Module).

- refer to No Power To The Scan Tool, to diagnose no power to the scan tool Pinpoint Test Z: No Power To The Scan Tool.


8. If the scan tool does not communicate with the vehicle:
- verify the ignition is ON.

- verify the scan tool operation with a known good vehicle.

- refer to Information Bus The PCM Does Not Respond To The Scan Tool, to diagnose no response from the PCM Pinpoint Test A: The PCM Does Not Respond To The Scan Tool.


9. Carry out the network test.
- If the scan tool responds with no communication for one or more modules, refer to Information Bus.

- If the network test passes, retrieve and record Continuous Memory Diagnostic Trouble Codes (CMDTCs).


10. Clear the continuous DTCs and carry out the self-test diagnostics for the ABS module.

11. If the DTCs retrieved are related to the concern, go to ABS Module DTC Chart Anti-Lock Brake System (ABS) and Stability Control. For all other DTCs, refer to the Master DTC Chart in Body Control Systems.
12. If no DTCs related to the concern are retrieved, GO to Symptom Chart. Symptom Related Diagnostic Procedures