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Diagnostic Strategies

A/T DIAGNOSTIC TROUBLESHOOTING STRATEGY
Use these steps to plan your diagnostic strategy. If you follow them carefully, you will find most A/T malfunctions.
1. Gather as much information as possible about the complaint from the customer.
2. Verify that the condition described by the customer exists.
3. Check the vehicle for any A/T Diagnostic Trouble Codes (DTCs).
4. If you can not verify the condition and there are no DTCs, the malfunction is intermittent.
5. If you can verify the condition but there are no DTCs, or the system can not communicate with scan tool, refer to the Symptom Chart. Symptom Chart
6. If there is a DTC, record the number of the code, then erase the code from memory using scan tool.
7. Reconfirm the symptom with a Road Test.
8. If a DTC is set again, go to the Inspection Chart for Diagnostic Trouble Codes. Diagnostic Trouble Code Descriptions
9. If a DTC is not set again, the malfunction is intermittent.
10. After repairs are completed, conduct a Road Test duplicating the complaint conditions to confirm the malfunction has been eliminated. Road Test