Initial Inspection and Diagnostic Overview

1. Verify the customer concern by operating the system.

Visual Inspection Chart:

2. Visually inspect for obvious signs of mechanical and electrical damage.
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 diagnostic tool to the Data Link Connector (DLC) located beneath the instrument panel and select the vehicle to be tested from the diagnostic tool menu. If the diagnostic tool does not communicate with the vehicle:
^ check that the program card is correctly installed.
^ check the connections to the vehicle.
^ check the ignition switch position.

5. If the diagnostic tool still does not communicate with the vehicle, refer to the diagnostic tool manual.
6. Carry out the DATA LINK DIAGNOSTIC TEST using the diagnostic tool. If the diagnostic tool responds with:
^ CKT 914, CKT 915 or CKT70 = ALL ECUS NO RESP/NOT EQUIP, go to Communication System Diagnostics in Module Communications Network (Information Bus) to diagnose network concern.
^ NO RESP/NOT EQUIP for Powertrain Control Module (PCM), turn the A/C function selector switch to OFF and execute Self-Test Diagnostics for PCM.
^ SYSTEM PASSED, retrieve and record the continuous Diagnostic Trouble Codes (DTCs), erase the continuous DTCs and carry out the self-test diagnostics for the PCM.

7. If the DTCs retrieved are related to the concern, go to the Powertrain Control Module (PCM) Diagnostic Trouble Code (DTC) Index to continue diagnostics. Diagnostic Trouble Code Tests and Associated Procedures
8. If no DTCs related to the concern are retrieved, proceed to the Symptom Chart. Symptom Related Diagnostic Procedures