Central locking - drivers door no longer initiating other locks

[Space_coyote]

Hi all! Hope you're having a great weekend. The below question is for my 2000 M52TU 2.0L Z3

Up until yesterday my central locking worked fine from the key fob, with the exception of the drivers door which hasn't worked since I've owned it. By manually locking/unlocking the drivers door with the key the central locking would initiate on the passenger door and boot/trunk - using the key in the drivers door lock has therefore always been my usual way of locking/unlocking the car.

Yesterday when locking the drivers door with the key the central locking on the passenger side and boot/trunk locked as usual, but then immediately unlocked again (I'd not unlocked the driver door). I tried locking/unlocking the drivers door using the key a few times and kept getting the same result. Central locking for passenger side and boot/trunk still works fine from the key fob.

Today when locking the drivers door with the key, there's no response from the central locking at all (i.e. it's no longer doing the lock followed by immediate unlock that it was doing yesterday). Again, central locking for passenger side and boot/trunk still works fine from the key fob. I've also confirmed that manually locking the boot with the key does initiate the central locking on the passenger door, as usual. My car doesn't have an external lock on the passenger side so can't try the key manually there.

I'm assuming that this is a problem with the drivers side lock actuator/wiring. However, I though it was unusual that yesterday the drivers door would initiate the central locking but it would then immediately unlock itself. It's possible that in the process of locking the drivers door with the key yesterday I bumped a button on the fob at the same time - could this cause the driver's door lock to disengage from the central locking system or something like that?

Anyone experienced this or got any thoughts before I start dismantling the drivers door?

 

[Mint]

I'd have a look at the so called 'loom of doom' before taking off the door card, unless you feel it's a mechanical problem with the lock itself.
The loom of doom is the wiring which goes into the boot/trunk lid from the body. Over time the constant flexing of the wires leads to insulation breakdown causing all sorts of alarm/central locking issues. You'll need to remove the outer insulation then check the wires inside. They can be repaired with soldering and heat shrink tubing or if really bad the is a replacement loom which can be patched in. HTH.

 

[DrWong]

I repaired my loom and this restored central locking from the key fob. In my case, the broken loom kept tripping the central locking fuse. Agree with Mint, the loom is probably the better place to start given the description of the problem, and much less involved than dismantling a door card.

 

[Space_coyote]

Hi guys, thanks for your suggestions. I removed the wrapping and checked the loom this morning, no visible broken or exposed wires so I’m back to thinking it must be the something in the driver’s door. Possibly the actuator hasn’t been unable to lock/unlock the driver’s door, but was still taking input from the key turning the lock, and that too has now stopped working…

 

[Mint]

At least you can eliminate the loom of doom wiring from the problem now. Looks like it's the door card off for a good look inside next They're easy enough to get off but they sometimes put up quite a bit of a fight to get them back on. Good luck.

 

[RTV]

In my case, passenser door wasn't opening/closing. I replaced the actuator and voila! working perfectly with both the key and alarm fob.

My symptom was that I had to use the key fromt he passenger to unlock driver and boot, so similar to you but the other way around. That told me that it was the actuator itself not activating. I suppose that it'll be easy to put a multimeter and see if 12v are being sent to activate the actuator and if that's the case that might be your issue.

I got a cheap replacement from amazon, worked like a charm. Tight fit, but doable.

 

[ATM]

Is your battery healthy? My battery a bit weak not helped by its winter rest, central locking sometimes gets temperamental. A good recharge seems to sort the issue. Worth a try before tearing things apart?