Driver's Door Lock Actuator Seized & Driver's Seat Motor Stopped Working

[Youdey]

My 2003 Z4 Driver's Door Lock Actuator seems to have seized, as I can't open the door from the outside or the inside of the car. I have had issues in the past opening the door using the key fob, as the driver's side didn't want to lock & unlock, so I have had to use the physical key. The passenger door & petrol cap all lock & unlock fine, so I don't think it would be an electrical issue, but I am not certain. I have tried the central locking button inside the car, which locks & unlocks the rest of the car fine but not the driver's door. I have taken the door card off & have accessed where the cables attach to the actuator to make sure that they have not stretched. They are fine & pull the levers enough to open the door. The white plastic clip that goes up & down to show if the door is locked is stuck in the down position, which means it is locked & I haven't been able to get it to unlock at all. I am currently stuck as to what to do & believe my only option left is to try drilling into the mechanism. If anyone has any experience or advice about this, then please let me know.

Along with the Driver's Door Lock Actuator being seized, the Driver's Seat Motor also stopped working. I have checked the fuse & unfortunately it wasn't that. I am a little stuck on where to start with that, as I currently can't open the door to have a proper look at it.

 

[enuff_zed]

I’m away on holiday with limited access to check stuff, but somewhere in the E85 How To section I have put a detailed description of how to get the door open. It will mean you need a new actuator but it sounds like yours has died anyway and the likes of @Umfaan should be able to supply a spare.

 

[Youdey]

I’m away on holiday with limited access to check stuff, but somewhere in the E85 How To section I have put a detailed description of how to get the door open. It will mean you need a new actuator but it sounds like yours has died anyway and the likes of @Umfaan should be able to supply a spare.

Thanks, I'll try to find it. I had actually got a replacement as I knew it needed doing, but I just hadn't gotten around to replacing it.

 

[enuff_zed]

Thread 'Removing a door lock that will not open'

Mar 31, 2025

I have experienced the problem that I’ve heard a lot about in the past and dreaded happening to me.
Door closed and locked, press the key fob, or turn the key in the lock and the knob pops up but the door remains stubbornly shut. Unable to be opened from either the inside or the outside.
This is caused by an internal failure within the lock assembly and you are pretty much stuffed as you cannot remove the lock because two of the mounting screws are on the rear edge of the door.
If you are really lucky it may just be down to a build up of grime inside and a liberal soak with WD40 or similar...

• enuff_zed
• Replies: 0
• Forum: HOW-TO Submissions

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[Youdey]

Thought it was worth posting an update if others have the same issue. The door actuator went into deadlock & wouldn't come out. In the end, I had to take the door card off with the door shut which was a nightmare, especially when trying to blindly unplug the electrical connections on the door card. Once I had the door card off, I tried to see if there was anything I could do to unlock the door but there wasn't. There seems to only be 2 ways to get your door out of deadlock, the first is to manually send electric signals to the right wires/pins to take the door out of deadlock and the second method is to drill/break into the actuator so it releases. I ended up manually sending electric signals to the right wires/pins. I had an old car battery that I had recently replaced from another car, I used that & some old wires that were left over from house renovations. You need to send the negative signal to the top pin which is the black wire, the positive goes to pin beneath it which is the blue wire. I will worn that the pins are very close together so it is a very delicate job that you will probably need someone else with you to connect the wires to the battery once you have them on the right pins. If you have a spare door wiring loom, then you can plug that into the actuator & use the end of the wires that plug into the car body to send the signals through, the wires you need are the same (positive to the blue wire, pin 20, & negative to the black wire, pin 21). When the signal has been sent to the actuator, you'll hear what sounds like it unlocking but the actuator will still be in the locked position, you should just need to pull the interior door handle twice, once to unlock & a second to open the door. Please be aware that because the door has been unplugged then the window won't drop down so you should have the window down when unlocking the car, as I had already unplugged the door card, I just put the roof partially down so that the windows went down slightly.