Abs Diagnostic Troubleshooting Strategy

Use these steps to plan your diagnostic strategy. If you follow them carefully, you will be sure that you have exhausted most of the possible ways to find an ABS fault.

1. Gather information about the problem from the customer.
2. Verify that the condition described by the customer exists.
3. Check the vehicle for any ABS DTC.
4. If you cannot verify the condition and there are no ABS DTCs, the malfunction is intermittent. Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTIONS .
5. If you can verify the condition but there are no ABS DTCs, or the system cannot communicate with the scan tool, check that the basic brake system is operating properly.
   • If the basic brake system is not operating properly, refer to the BASIC BRAKE SYSTEM DIAGNOSIS .
   • If the basic brake system is operating properly, refer to SYMPTOM CHART  .
6. If there is an ABS DTC, record the number of the DTC, then erase the DTC from the memory using the scan tool.
   NOTE: Any DTCs stored in the ABS-ECU cannot be erased if there is a malfunction.
7. Duplicate the ABS DTC set conditions to see if the same ABS DTC will set again.
   • If the same ABS DTC sets again or the ABS DTC cannot be erased, perform the diagnostic procedures for the DTC. Refer to DIAGNOSTIC TROUBLE CODE CHART  .
   • If you cannot get the same ABS DTC to set again, the malfunction is intermittent. Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTIONS .