Initial Inspection and Diagnostic Overview

Inspection and Verification

1. Verify the customer concern by duplicating the condition.
2. Visually inspect for obvious signs of mechanical and electrical damage.

Mechanical
- Large metallic objects, a second ignition key on the same key ring as the PATS ignition key or electronic devices on the key chain that can be used to purchase gasoline or similar items
- Ignition lock cylinder
- PATS key
- Use of a non-PATS key
- More than one PATS key on key chain

Electrical
- Central junction box (CJB) fuse:
- 19 (25 A).
- 28 (7.5 A).

- PATS transceiver module
- PCM
- Ignition switch
- Loose or corroded connection(s)

3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
4. If the concern remains after the inspection, connect the WDS or equivalent tester to the data link connector (DLC) located beneath the instrument panel and select the vehicle to be tested from the WDS or equivalent tester menu. If the WDS or equivalent tester does not communicate with the vehicle:
- Check that the program card version 6.0 or later is properly installed.
- Check the connections to the vehicle
- Check the ignition switch position.

If the WDS or equivalent tester still does not communicate with the vehicle, refer to the Symptom Troubleshooting Chart in this section.

5. If the WDS or equivalent tester responds with:
- NO RESP/NOT EQUIP for PCM. See MODULE DOES NOT RESPOND TO THE WDS TESTER (PCM).
- SYSTEM PASSED. Retrieve and record all PATS Continuous DTCs, clear the Continuous DTCs and perform the Self-Test for the PCM.

6. If the DTCs retrieved are related to the concern, go to the PCM Diagnostic Trouble Code (DTC) Index to continue diagnostics.
7. If no DTCs related to the concern are retrieved, refer to the Symptom Troubleshooting Chart to continue diagnostics. Symptom Diagnostic Index