Initial Inspection and Diagnostic Overview
Inspection and Verification1. Verify the customer concern.
2. Verify the stoplamps operate correctly by pressing and releasing the brake pedal with the ignition switch in the OFF position. If the stoplamps operate correctly, proceed to the next step.
3. Verify that the PRNDL operates correctly on the instrument 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. If the concern remains after the inspection, connect the diagnostic tool to the data link connector (DLC) located beneath the instrument panel, 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 connection of the data link connector to the vehicle.
^ check that the ignition switch is in the RUN position.
7. If the diagnostic tool still does not communicate with the vehicle, refer to the diagnostic tool operating manual.
8. NOTE: The battery voltage must be greater than 9.4V for the self-test to operate correctly.
Carry out the diagnostic tool data link test. If the diagnostic tool responds with:
^ CAN or ISO circuit fault; all electronic control units no response/not equipped, refer to Information Bus (Module Communications Network).
^ No response/not equipped for the ABS module, GO to Pinpoint Test A. A: No Communication With the Anti-Lock Brake Control Module
^ System passed, retrieve and record the continuous diagnostic trouble codes (DTCs), erase the continuous DTCs and carry out the self-test diagnostics for the ABS module.
9. If the DTCs retrieved are related to the concern, go to the Anti-lock Brake System (ABS) Module Diagnostic Trouble Code (DTC) Index to continue diagnostics. [1][2]Diagnostic Trouble Code Descriptions
10. If no DTCs related to the concern are retrieved, GO to Symptom Chart to continue diagnostics. Symptom Related Diagnostic Procedures