Initial Inspection and Diagnostic Overview
Inspection and VerificationNOTE: If a new ABS module is installed, it must be configured. Refer to Information Bus. If equipped with stability assist, the ABS module must also be calibrated. Follow the diagnostic tool directions.
1. Verify the customer concern.
2. Verify the stoplamps operate correctly by applying and releasing the brake pedal with the ignition switch in the OFF position. If the stoplamps operate correctly, proceed to the next step.
3. Visually inspect for obvious signs of mechanical or electrical damage.
Visual Inspection Chart
4. If the cause is not visually evident, connect the diagnostic tool to the data link connector (DLC) and select the vehicle to be tested from the diagnostic tool menu. If the diagnostic tool does not communicate with the vehicle:
^ check that the program card is correctly installed.
^ check the connections to the vehicle.
^ check the ignition switch position.
5. If the diagnostic tool still does not communicate with the vehicle, refer to the diagnostic tool operating manual.
NOTE: If equipped with stability assist, the vehicle must be at a complete standstill when carrying out the self-test. Any movement of the vehicle during the self-test may result in false DTCs being set.
6. Carry out the diagnostic tool data link test. If the diagnostic tool responds with:
^ SCP, ISO, or CAN circuit fault; all electronic control units no response/not equipped, refer to Information Bus.
^ No response/not equipped for the ABS module, GO to Pinpoint Test A. Test A: No Communication With the Anti-Lock Brake System (ABS) Module
^ System passed, retrieve and record the continuous diagnostic trouble codes (DTCs), erase the continuous DTCs, and carry out self-test diagnostics for the ABS module.
7. If the DTCs retrieved are related to the concern, go to the Anti-Lock Brake System (ABS) Module Diagnostic Trouble Code (DTC) Index Anti-Lock Brake System (ABS) Module Diagnostic Trouble Code (DTC) Index to continue diagnostics.
8. If no DTCs related to the concern are retrieved, GO to Symptom Chart Symptom Related Diagnostic Proceduresto continue diagnostics.
NOTE: The need to recalibrate the module is indicated by the active/fail lamp flashing. There are other service actions that can require recalibration when there is no flashing lamp. The lamp will flash after clearing the DTCs that are indicated in the ABS module calibration list.
NOTE: Always retrieve the continuous DTCs after running the self-test.