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.
Rear 12 V socket
When a power consuming component is connected to the rear 12V socket (17/19), the power consumption is measured via a directly connected shunt (20/39) on the rear electronic module (REM) (4/58). The rear electronic module (REM) transmits status data via the control area network (CAN) to the driver information module (DIM) (5/1) which displays a text message (applies only to factory mounted 12V sockets).
The text message is also displayed if a power consuming component is connected when changing from ignition position:
- II to I
- I to 0 and
- 0 to the key is removed.
There is also an audible warning note when the key is removed.
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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