Possible Causes
| Possible Causes |
|---|
| ENGINE BRAKE DTCS PRESENT |
| ABS DTCS PRESENT |
| (L51) BRAKE SWITCH SIGNAL SHORT TO GROUND |
| SHIFT LEVER ASSEMBLY |
Always perform the NAG1 Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to DTC-Based Diagnostics/MODULE, Transmission Control (TCM) - Standard Procedure .