Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Transmission Control Module - Diesel Engine
| 1 -TCM |
If the vehicle is equipped with a NAG1 transmission the TCM (1) is a separate module located behind the drivers knee bolster to the right of the steering column. The TCM uses the Controller Area Network (CAN) C high-speed intra-vehicle communications network to deliver commands to the transmission and monitor operations. A module on the automatic transmission shifter communicates range selection data to the transmission, also using the CAN-C network. This information is also displayed in the instrument cluster.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.