Diagnostic Troubleshooting Strategy

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. (Refer to, Diagnostic Function - How to Read and Erase Diagnostic Trouble Codes).
4. If you can verify the condition but no auto-cruise control system DTCs are set, 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 MB991958 (M.U.T.-III sub assembly), and find the fault. (Refer to, Symptom Chart).
6. If there is an auto-cruise control system DTC, record the number of the code, then erase the code from PCM memory using the scan tool MB991958 (M.U.T.-III sub assembly). (Refer to, Diagnostic Function - How to Read and Erase Diagnostic Trouble Codes).
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).