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Diagnostics




Diagnostics

OBD (On-Board Diagnostic) with Scan Tool

These self-tests should be used to diagnose the TCM (Transmission Control Module) and should be carried out in order.

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

1. If the cause is not visually evident, connect the scan tool to the DLC (Data Link Connector).

NOTE: The VCM (Vehicle Communication Module) LED prove-out confirms power and ground from the DLC (Data Link Connector) to the VCM (Vehicle Communication Module).

2. 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 Information Bus to diagnose no power to the scan tool.


3. If the scan tool does not communicate with the vehicle:
- verify the ignition is in the RUN position.

- verify scan tool operation with a known good vehicle.

- refer to Information Bus to diagnose no response from the TCM (Transmission Control Module).


4. Carry out the network test.
- If the scan tool responds with no communication from one or more modules, refer to Information Bus.

- If the network test passes, retrieve and record the continuous memory DTCs.


5. Clear the continuous DTCs and carry out the TCM (Transmission Control Module) self-test.

6. If DTCs retrieved are related to the concern, GO to the DTC Chart Automatic Transmission/Transaxle.

7. If no DTCs related to the concern are retrieved, GO to Diagnosis By Symptom Diagnosis By Symptom.