I have a 2009 C-300. Last week went for regular A service, they also changed FLEX DISC for $440, saying it was cracked.
This morning car wont start. I will have to tow it to dealership next week. My battery is original Mercedes, changed 18 months ago. I read online, some said its ignition switch or may be steering lock or even starter relay. But everyone had slight different symptoms. So I will explain mine in detail. When I insert key, I do not hear the zzzzip sound. The key TURNS NORMALLY. ONLY cluster display comes on, showing date & mileage. But Engine or gas or ABS light does NOT come on. The gear shift is locked. Windows do NOT roll down. Dash board back lights are on, but when I switch the headlights on through the knob on left, the dash lights go away, come back on when turn headlights to off or auto position. I thought it was the battery since the headlights wont turn on and the dash lights turn off thinking headlights taking all the juice. The voltage on battery is 12.25 V. My friend brought his X6, we connected cables, but still EXACTLY the same. Even the headlight won’t turn on despite being connected to the other car, I checked the voltage and it was 13.75 on the terminals (while connected to the running bmw). I checked the starter fuses, 6,7,19,27. They are OK. I saw a video describing similar problem caused by starter relay, but in that video the engine, ABS and gas lights were turning on when turning the key, mine does NOT. So I did not buy a relay as it may be a different problem.
I am just trying to save money on towing it, if it is something that I can fix at home. I have a fear that it would be one of those $1200 thing everyone is taking about with the steering. Please advise me if you can ….. thank you in advance.


This condition is usually the ESL module or the ESL motor is bad. Very common. (Electronic Steering Lock)

There's not much else to say or that can be done DIY to test or fix for this problem without a GOOD diagnostics scanner.

The zzzzzzzzpt sound is the esl moving the bolt for the steering lock. When you do not hear this noise when inserting your key then its usually because the motor in esl has died (or sometimes the key has lost synchronization).

If your really mechanically inclined you can swap the motors in esl but the ESL module itself is a restricted part and you need special security privileges to buy the replacements from Mercedes. The ESL is part of the starting authorization chain so if its not releasing then there will be no crank. On early model Mercedes the ignition would not even turn.

  • 1
    While this may be true, explaining why you believe it may be this and how the OP would go about testing to prove it would make it a much better answer. – Pᴀᴜʟsᴛᴇʀ2 2 days ago

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