Four Wheel Drive (4WD) Systems - 2-Speed Torque-on-Demand
Four Wheel Drive (4WD) Systems - 2-Speed Torque-On-Demand
Inspection and Verification
1. Verify the customer concern.
2. Visually inspect for obvious signs of mechanical or 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. NOTE: Make sure to use the latest scan tool software release.
If the cause is not visually evident, connect the scan tool to the Data Link Connector (DLC).
5. NOTE: The Vehicle Communication Module (VCM) LED prove out confirms power and ground from the DLC (Data Link Connector) are provided to the VCM (Vehicle Communication Module).
If the scan tool does not communicate with the VCM (Vehicle Communication Module) :
- check the VCM (Vehicle Communication Module) connection to the vehicle.
- check the scan tool connection to the VCM (Vehicle Communication Module).
- refer to No Power To The Scan Tool, to diagnose no power to the scan tool Pinpoint Test Z: No Power To The Scan Tool.
6. If the scan tool does not communicate with the vehicle:
- verify the ignition is in the ON position.
- verify the scan tool operation with a known good vehicle.
- refer to Information Bus to diagnose no response from the PCM.
7. Carry out the network test.
- If the scan tool responds with no communication for one or more modules, refer to Information Bus.
- If the network test passes, retrieve and record Continuous Memory Diagnostic Trouble Codes (CMDTCs).
8. Carry out the self-test diagnostics for the TCCM (Transfer Case Control Module).
9. If the DTCs retrieved are related to the concern, go to the TCCM (Transfer Case Control Module) DTC Chart Four Wheel Drive (4WD) Systems - 2-Speed Torque-on-Demand. For all other DTCs, refer to Body Control Systems.
10. If no DTCs related to the concern are retrieved, GO to Symptom Chart- Four-Wheel Drive System Four Wheel Drive (4WD) Systems - 2-Speed Torque-on-Demand or GO to Symptom Chart- NVH Four Wheel Drive (4WD) Systems - 2-Speed Torque-on-Demand.