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 **** 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.

 

Hello and welcome to the forum! Before spending any money, I would suggest getting the codes read. This should give you a great place to start troubleshooting and will likely lead you to the issue itself. Hope this helps you a bit and best of luck.

 

I connected the ODB reader but it didn't read any codes.
anyway, towed it to the dealer, he said its the steering lock and will cost 990$ he said they read the code. may be they have a different device to read codes.

 

You should inquire what codes they read. I'm also attaching a link to the DIY tech article on the steering lock replacement procedure. If you're interested in a great code scanner that can also reset codes, look at the second link below.

Electronic Steering Lock Replacement

Schwaben Pro Scan Tool for Mercedes Benz