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How to Fix the Ignition Switch Problem on the Mercedes-Benz C-Class W203

Model: Mercedes Classe C W203 - Years: 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007
Part: Key

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Video tutorial

The ignition switch on the Mercedes-Benz C-Class W203 is known for its issues: the key gets stuck in position "0" (steering locked) or in position 1 (system on). Sometimes it turns without engaging, and sometimes it locks after being turned off. The main causes are a worn ignition cylinder: the internal brass tabs wear out and no longer catch the key; or the electrical interlock (the module that recognizes the key and unlocks the gear lever) fails and won't go beyond position 1. It can also be a problem with the gear lever not being in "P" or "N" position, causing the system to lock the ignition for safety.

A temporary solution is to slightly move the steering wheel, the gear lever, or press the brake hard to activate the interlock.

The definitive solution is to replace the ignition cylinder, but it is very expensive. Some shops install a bypass to skip the faulty module, but this disables part of the anti-theft system.

Despite these issues, Mercedes has never issued an official recall for this defect. Avoid DIY solutions for this problem: you risk making it worse.


Posted on 28 March 2026 by ScegliAuto


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