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.
Back-Up Lamp
There are two reversing lights located in the tail lights. The reversing lights come on when reverse gear is selected. The reversing lights are connected to the central electronic module (CEM) via a directly connected relay. The lamps are powered via the relay.
Cars with manual transmissions
Cars with manual transmissions have a back-up (reverse) switch on the transmission. The switch closes and transmits a directly connected signal to the central electronic module (CEM) when back-up (reverse) gear is selected.
Cars with automatic transmissions
In cars with automatic transmissions, a signal is transmitted from the transmission control module (TCM) on the controller area network (CAN) to the central electronic module (CEM) indicating that back-up (reverse) gear is selected.
To detect faults in the reversing lights, the central electronic module (CEM) reads power consumption in the circuit. If the power consumption falls below a certain limit, a fault is indicated and a text message is displayed in the driver information module (DIM).
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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