2003 230SLK, 42,000mi

As of today, my driver door no longer locks by itself using the key fob, interior switch, or at speed when driving. The other locks in the vehicle work perfectly.

I went to the Stickie, and it seemed to deal with the PSE getting wet and not operating properly. I don't think this applies to my car since it's never driven in the rain, and is always garaged (and only seldom used on blue-sky days).

Problem:

The driver's door works fine using the key to lock/unlock mechanically and does activate the locking system, with the passenger door and trunk locking properly.

The driver's door DOES UNLOCK automatically by the vacuum pomp using any method that opens the passenger door and other vacuum locks.

If I partially depress the driver's door locking button manually with my finger (when commanding the door to lock using the vacuum system), at about 1/2, the button is sucked fully into the locked position as it should be.

If I understand the system, my pump module in the trunk IS working properly, and I most likely have either:

1) A sticking actuator or driver's door lock... OR
2) A faulty vacuum actuator in the driver's door itself...
3) A leak in the hose from the PSE to the driver door actuator (though if this were true, I wouldn't expect the door to unlock with such authority, which it does, as well and as fast as the passenger door lock button).

Could someone confirm or rule-out my diagnosis before I remove the driver's door inner panel please?

Is there a diagram showing which hose on the PSE goes to the driver's door so I could try disconnecting it at the pump module, and by sucking on it see if the actuator locks (this may show me if there's a leak in the line)?

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Question 2

I have not previously removed the door panel on the SLK, so could someone instruct me, or point me to a thread discussing it?

I would guess there are screws under the door pull handle, but I don't want to improperly force the cover off the handle and break it. I would also guess there may be a screw under the inner door latch after the black plastic cup under the latch handle is pried off? Does the rest of the panel "pop" off by prying between the cover and the steel door shell, and can the cover be lowered w/out damaging the door speaker leads, or other wires?

Much appreciated-
Bob

 

I suspect that if you can get the actuator out and clean it it should be OK since it is partially working.
Here is a link on the removal.

http://www.pelicanparts.com/techarti...el_Removal.htm

 

Thanks!

I found a Pelican link on removing the lock parts, but the one you forwarded on safe (non-destructive) removal of the interior panel was most helpful.

I tend to agree that the problem is a stiff latch-lock, or a lazy actuator.

Last evening, I went out to get something from the vehicle, and amazingly, the driver's door lock worked pretty much as advertised, though it took about twice as long to lock as the passenger door, though it unlocked in the same amount of time as the passenger door.

That left me believing that the problem is, indeed, isolated in the actuator, as you suggest, and/or possibly a lock possibly in need of lubrication.

Thanks,
Bob

 

OK, Got the inner door panel off, and located where the vacuum line plugs into the lock actuator using a small plastic right-angle fitting that presses into the vacuum line, and snaps over the port on the actuator.

Upon removing the fitting from the actuator, the right-angle fittin was cracked (and finished breaking off upon removal).

I tried to cross reference the part number on it without luck. What I can read is 3 012508/3.

Below are two links for photos of the part if anyone can help me identify it.

I am going to post a separate thread in case few people are following this thread as well.

Thanks!

Click On:

1) http://screencast.com/t/mCUoawPZ5JD (Red arrow points to broken-off male hose fitting)

2) http://screencast.com/t/unbVifrbaTh (Red arrows approximate size of broken-off male hose fitting)

UPDATE- Since I cannot delete a post, only edit it, I'll pass along that I managed to cross-reference it to MB Part A 202 8000 453

With the right angle adapter removed, I slipped a length of windshield washer hose over the actuator nipple itself, and with the door latch closed (door open) the lightest amount of sucking or blowing by mouth effortlessly worked the lock BOTH ways, so the actuator and lock are fine. I suspect it was a cracked nipple on the right angle adapter itself given how it literally fell apart when disturbed. The hose was REALLY tight, with zero slack, so I'm guessing it was under a lot to tension and just failed at the weakest point.

I have ordered a couple from Pelican, and if the lock doesn't work then, I probably have an air leak somewhere else, hopefully somewhere easy like at the PSE itself in the trunk where I can access it, but hopefully not a broken nipple!