Auto-Cruise Control System Diagnostic Troubleshooting Strategy

Use these steps to plan your diagnostic strategy. If you follow them carefully, you will check most of the possible causes of an auto-cruise control system problem.

1. Gather information from the customer.
2. Verify that the condition described by the customer exists.
3. Check the vehicle for any auto-cruise control system DTC.
4. If you can verify the condition but no auto-cruise control system DTCs are set, and the malfunction may be intermittent.
5. If you can verify the condition but there are no auto-cruise control system DTCs, or the system cannot communicate with scan tool MB991502, refer to SYMPTOM CHART  and find the fault.
6. If there is an auto-cruise control system DTC, record the number of the code, then erase the code from vehicle memory using the scan tool.
7. Re-create the auto-cruise control system DTC set conditions to see if the same Auto-cruise Control System DTC will set again.
   • If the same Auto-cruise Control System DTC sets again, perform the diagnostic procedures for the set code. Refer to DIAGNOSTIC TROUBLE CODE CHART , Auto-cruise Control System Diagnostic Trouble Code Chart.