Driver side door won't lock
 

Hello All,

New owner here. Recently acquired a well maintained 03 SL55.

First problem i am trying to tackle is driver side door refuses to lock.
Passenger door locks fine, trunk locks fine, but on the driver side i see the lock button next to the window goes in only half way.
I cannot push it manually to go all the way in from inside. I cannot lock it with the key either from outside.
It feels like there is something preventing/pushing back on the lock button and it can go in only half way.
As a result, my driver side door stays unlocked while the rest of the car is locked. The alarm goes on if i open the door, so the alarm is clearly armed.

Any ideas where to start? Should i get a new lock actuator? Any other tips?

Thank you!

door lock
 

Welcome to the forum! You'll need to get the door panel off and see what is causing this. It may be a leaking actuator which may be repairable with epoxy like the trunk latch. Could be vacuum line leak or partial break also. From your description though it may be just "hung up" somewhere and not require any new parts, just jammed up for some reason.

moretech

Did you or anyone fixed it?
I'm having exactly same problem.

Find on this forum how to get the door panel off (not at all difficult but with some need-to-knows) and simply look for a mechanical blockage in there.

Any help?
 

I am having the exact same problem. Did anybody else know how to fix this?

hey I had same issue.
The problem is vacuum pump, you need to check yellow line where it's broken, so in my case line was broken on vacuum pump itself, if there's nothing then you need to take door cover off and look there, usually it would break where all cable goes to chasing from door.

But I think, if problem is vacuum, you should be able to push down lock button (the thing on the door, when you lock car, it goes down, if you can't oush it in, it means it has vacuum and oroblem is mechanism itself so I was told)

Lock problem is not the vacuum pump.
 

It's not the vacuum pump as the door will:

1. start to lock but not go all the way into the locked position when using the push button on the dash or the remote, and
2. when attempting to use the key to manually lock the door it will go almost to the locked position but not lock and the door can still be opened.

Something is definitely preventing it from completely locking. When I open up the door skin cover at the lock I can see a bright green mechanism that looks like the arm of the black plastic locking mechanism is supposed to either rotate or prevent rotation however it looks like it doesn't seat into the green mechanism correctly.

Tony