99 bmw 328i door lock problem

[Wayne 962]

A customer asked me this via email:

My mechanic and I have tried to figure out what we can do about my locks not wanting to work. His computer will not talk to my computer as of now. This car was hit in the rear before I got it, The remote switch works always to lock the doors but will not unlock half the time, not even from the inside switch and sometimes the handels will not let you get out either. My passangers and I would have to break the glass to get out if there were a real emergency. Once the locks are engaged I've tried moving the car forward a few feet and sometimes they'll unlock, but after several tries from the inside switch, it will lock it up completely.

I have not taken it back to the dealer from which I purchased it from 2 years ago, it was a BMW dealer too and that was not a problem at the time. They had all the records from the previous ower and I did get them to do a through check of the car before I bought it.

It's a puzzle for us, got any clues?

Lee

Hi there. This could be caused by a number of things, and yes, it is difficult to track down.

- The locking computer may be suspect, or there may be some type of aftermarket alarm installed (or factory) that you don't even know about. This happened on one of my own BMW 3 Series cars - didn't know about the alarm until I opened the glove box.

- Trunk wiring. See the picture in "solving electrical problems" in the 101 Projects book. Short circuits in the trunk can cause problems like these.

- Defective or failing gauge cluster. I have heard of problems like these being caused by a bad cluster, but they are rare.

- Door lock switches. If the door lock switches are broken, then this could exhibit some of this behavior. These are the switches that are inside the electric lock motors.

Personally, it sounds like a bad lock computer or alarm system to me...

-Wayne