Initial Inspection and Diagnostic Overview

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TRANSFER CASE ELECTRONIC SHIFT ON - BOARD DIAGNOSIS

Inspection and Verification

1. Verify the customer concern by operating the system in question.

2. Visually inspect the following for obvious signs of mechanical and electrical damage.
Visual Inspection Chart





3. If an obvious cause for an observed 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 scan tool to the data link connector (DLC).

NOTE:The vehicle communication module (VCM) LED prove out confirms power and ground from the DLC are provided 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 or to the diagnose no communication with the scan tool.

6. If the scan tool does not communicate with the vehicle: See Communications Network. No response from the powertrain control module (PCM).

7. Carry out the network test

- If the scan tool responds with no communication for one or more modules, see Communications Network.
- If the network test passes, retrieve and record continuous memory diagnostic trouble codes (DTCs).

8. Clear the continuous DTCs and carry out the self-test diagnostics for the 4WD Control Module.

NOTE:Before carrying out the on-demand self test, make sure that the ignition is in RUN, all the door are closed, the brake pedal is not pressed, the transmission is in NEUTRAL (automatic transmissions) and the clutch pedal is not pressed (manual transmissions).
9. If the DTCs retrieved are related to the concern, see - DTC Index.

10. If no DTCs related to the concern are retrieve, see - Symptom Troubleshooting Chart - Driveline / Axle.