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Inspection and Verification




Anti-Lock Control - Traction Control and Stability Assist

Inspection and Verification

Identifying the Brake System

Two ABS systems are available for this vehicle: ABS enhanced with Engine Only Traction Control (EOTC) and ABS enhanced with traction control and stability assist. ABS with traction control and stability assist may also be called Electronic Stability Control (ESC), RSC(R) (Roll Stability Control), AdvanceTrac(R) or IVD by the scan tool and other service publications.

ABS with traction control and stability assist can be identified by the presence of individual left and right rear wheel speed sensors.

ABS with EOTC (Engine Only Traction Control) can be identified by the absence of rear wheel speed sensors.

To diagnose ABS with EOTC (Engine Only Traction Control), refer to Anti-Lock Control.

1. Identify the brake system.

2. Verify the customer concern.

3. Verify the stoplamps operate correctly by pressing and releasing the brake pedal with the ignition switch in the OFF position. If the stoplamps do not operate correctly, refer to Lighting and Horns. If the stoplamps operate correctly, proceed to the next step.

4. Verify the base brake system operates correctly. If any concerns are present, address them before continuing with any ABS concerns. If the base brake system operates correctly, proceed to the next step.

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

Visual Inspection Chart






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

7. 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).


8. 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.


9. If the scan tool does not communicate with the vehicle:
- verify the ignition key is in the ON position.

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

- refer to Information Bus to diagnose no response from the PCM.


10. 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).


11. Clear the CMDTCs (Continuous Memory Diagnostic Trouble Codes) and carry out the self-test diagnostics for the ABS module and the IPC (Instrument Panel Cluster).

12. If the DTCs retrieved are related to the concern, go to the ABS Module DTC Chart. Diagnostic Trouble Code Descriptions For all other DTCs, refer to Body Control Systems.

13. If no DTCs related to the concern are retrieved, GO to Symptom Chart Special Tool(s) Used With Diagnostics.