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.
Radio With 4-Digit Fixed Code (CL, S & SL Class)
Turn ignition on. Turn radio on. CODE will be displayed. Enter customer supplied code number using station number keys on radio. Confirm correct code by pressing SEEK button. Unit will turn on if correct code is entered.
If wrong code is entered 3 times, code entry is denied for 15 minutes. If wrong code is entered 9 times, code entry is denied for 24 hours. Radio and ignition switch must remain on during the waiting period.
NO RELATED
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.