W209 CLK Convertible - fob and key not working

[tintinmt]

We have a 2008 CLK convertible. The car is not responding to the key fob so we can't open the car at all. We have tried the spare and replaced the batteries in the fob. We have also tried using the manual key in the drivers door lock but it will not turn. Any advice please?
Thx.

 

[tintinmt]

RAC attended. Opened the car by prying the drivers door window with an air bag and pulling the internal door handle with a wire. Car started normally on the key. Diagnosis so far is that the mechanical lock is faulty - there is no connection between the lock and the door mechanism. There must be a fault in the 'ecu' for the unlocking.
Will book for repair of the above.
Moral of the story - check that your physical key works in your drivers door and boot.

 

[W4E300]

Thanks for the advice - I'm of to check mine out right now....(!)

Sent from my iPad using MBClub UK

 

[thecolonel]

oddly enough, my 'key' doesnt work in the drivers door on my ML either, just turns - is this a common problem / fix within these MB lock units out of interest?

what was your fix?>

 

[tintinmt]

My internet research did reveal other examples of this type of failure but not an obvious specific cure. I will update once we have the car repaired next week. Obviously, the problem is worse in a car where access to the interior cannot be gained via the rear door or boot. On a saloon or coupe you might easily damage the car to force entry, although the roadside assistance guys do seem to have experience of this.

 

[tintinmt]

Just out of interest I dismantled the broken lock - see image. The failure seemed to be in the black plastic ring to the left of the image. it sits between the metal lock barrel and the metal connecting rod that links to the door mechanism. At a guess I'd say it must have been designed to fail when forced? It's an obvious weak link.

 

[WOODYTHEWISE]

I have read several posts about emergency keys not working. The general consensus being that the locks through non/seldom use become very stiff. I think the trick is to use WD40 or the like and turn the key, strongly, left and right, apply more WD40 then repeat. some even left the lock to soak overnight. I had the same problem, the above fixed it. Remember the boot! Thank you for posting and the photograph.