W169 passenger door lock

[marksmith]

Hello,

The passenger door lock on my 2006 W169 A-Class is faulty. When you lock the car using the central locking, the pin bounces down-up-down-up-down-up quickly, often not managing to lock. It's getting worse, and it's worse in colder weather.

If you apply very gentle pressure to the top of then door pin while it's locking then it works fine first time. Conversely if you hold the pin gently up, it will fail, so I think something has just got a bit weak or is binding slightly.

I took the door card off hoping I'd find something to lubricate but I couldn't find anything accessible - it's all contained within the factory-riveted inner metal part. All that's visible is a length of rod with the door pin on top.

Any suggestions please?

Many thanks,
Mark

 

[Dave Richardson]

It seems that you're experiencing an old known problem with what was known as a machine gun rattle, caused by a weak or broken spring in the door lock, you could try e bay for a new spring & tools (cheap option) or replacement mechanism. It happened on my car some years ago now so mind may be a little rusty, no doubt others on her will be able to help you out