Inspection and Verification - Engine Performance

Engine

Inspection and Verification - Engine Performance

1. Verify the customer concern by operating the engine to duplicate the condition.

2. Visually inspect for obvious signs of mechanical damage. Refer to the following chart.

Visual Inspection Chart






3. If the inspection reveals obvious concerns that can be readily identified, repair as necessary.

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.


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.

- 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. Clear the continuous DTCs and carry out the self-test diagnostics for the PCM.

9. If the DTCs retrieved are related to the concern, go to the Master DTC Chart, Master DTC Index refer to Body Control Systems.

10. If no DTCs related to the concern are retrieved, GO to Symptom Chart- Engine. Symptom Related Diagnostic Procedures