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ABS Diagnostic Troubleshooting Strategy

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 use Troubleshooting/Inspection Service Points, How to Cope with Intermittent Malfunctions. Testing and Inspection
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 Basic Brake System Diagnosis under Brakes; Testing and Inspection.
- If the basic brake system is operating properly, refer to Diagnosis By Symptom.
6. If there is an ABS DTC, record the number of the DTC, then erase the DTC from the memory using the scan tool.
7. Recreate the ABS DTC set conditions to see if the same ABS DTC will set again.
- If the same ABS DTC sets again, perform the diagnostic procedures for the DTC.
- If you cannot get the same ABS DTC to set again, the malfunction is intermittent. Refer to How to use Troubleshooting/Inspection Service Points, How to Cope with Intermittent Malfunctions. Testing and Inspection