Initial Inspection and Diagnostic Overview

SPEED CONTROL

Inspection and Verification

1. Verify the concern.

2. Visually inspect for obvious signs of mechanical or 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.

4. Check to make sure the stoplamp switch is correctly seated in the brake pedal bracket.

NOTE:Make sure to use the latest scan tool software release.
5. 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 to the VCM.
6. 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 - Control System, No Power To The Scan Tool, to diagnose no power to the scan tool.

7. 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 - Control System to diagnose no response from the PCM.

8. Carry out the network test.

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

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

10. If the DTCs retrieved are related to the concern, go to DTC Charts. For all other DTCs, see - Diagnostic Trouble Code (DTC) Chart - B, C And U Codes.

11. If no DTCs related to the concern are retrieved, see - Symptom Related Diagnostic Procedures.

Speed Control DTC Charts

PCM DTC Chart