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.
Connection And Communication
Gen 1
The Transmission Control Module (TCM) is a CAN slave and a LIN master. For vehicles up to model year -2018 with a first generation VEA engine the Transmission Control Module (TCM) communicates via propulsion CAN and LIN.
Gen 2
For vehicles from model year 2018- with a second generation VEA engine there is an extra private CAN between the Transmission Control Module (TCM) and the Engine Control Module (ECM). The control modules are also connected to propulsion CAN and LIN, but primarily use the private CAN to intercommunicate.
Gen 3
For vehicles from model year 2020- with a third generation VED engine there are two different CAN (Front 3 CAN/ Front 1 CAN) between the Transmission Control Module (TCM) and the Engine Control Module (ECM).
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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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.