Initial Inspection and Diagnostic Overview

Inspection and Verification

1. Verify the customer concern.

Visual Inspection Chart:

2. Visually inspect for obvious signs of mechanical and electrical damage.
3. If an obvious cause for unobserved or reported concern is found, correct the cause if possible before proceeding to the next step.

NOTE: Make sure to use the latest scan tool software release.

4. If the cause is not visually evident, connect the WDS or equivalent tester to the data link connector (DLC).

NOTE: The vehicle communication module (VCM) LED prove out confirms power and ground from the DLC are provided to the VCM.

5. If the scan tool does not communicate with the VCM:
- Check the VCM connection to the vehicle.
- Check the scan tool connection to the VCM.
- See COMMUNICATIONS NETWORK, No power to the scan tool, to diagnose no communication with the scan tool.
6. If the scan tool does not communicate with the vehicle:
- Verify the ignition key is in the ON position.
- Verify the scan tool operation with a known good vehicle.
- See COMMUNICATIONS NETWORK, No power to the scan tool, to diagnose no communication with the scan tool.
7. Carry out the network test.
- If the scan tool responds with no communication from one or more modules, see COMMUNICATIONS NETWORK.
- If the network test passes, retrieve and record the continuous memory diagnostic trouble codes (DTCs).
8. Clear the continuous DTCs and carry out the self-test diagnostics for the SJB.
9. If the DTCs retrieved are related to the concern, GLASS, FRAMES AND MECHANISMS DIAGNOSTIC TROUBLE CODE (DTC) INDEX. Trouble Code Descriptions
10. If no DTCs related to the concern are retrieved,See A SYMPTOM TROUBLESHOOTING CHART Symptom Related Diagnostic Procedures
- POWER WINDOWS.