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.
Control Module
The trailer module (TRM) manages the electrical connection between the vehicle and the trailer.
The primary task of the control module is to manage output signals to the tow hitch cable harness for:
- Turn signal lamps
- Brake light
- Parking lamps
- Back-up lamp
- Fog lamps
- +12 V.
The trailer module (TRM) communicates on the controller area network (CAN) with:
- central electronic module (CEM)
- driver information module (DIM)
- differential electronic module (DEM) (option)
- parking assistance module (PAM) (option).
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.
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