Intermittent power locks

[JHZR2]

My 91 BMW is having funny lock behavior.

Over a year ago, when it was really hot out, the whole car would unlock keyless, but the drivers side would not make it all the way up. As soon as it got cooler, all was well.

Then that went away.

Lately, the car will not unlock at all, and when I do it manually (key at ds door or trunk should unlock the whole car), nothing happens in any door but the one I'm using the key on.

However, the lock function works as designed. And, the entire thing works sometimes out of the blue, like today, perfectly and completely.

Even when not working, I hear a relay click for unlock from the kickpanel where the lock brain is.

A few weeks back, the ps lock was stuck down. Sometimes each of them is tougher to move than other times.

Any ideas or suggestions?

Thanks!

 

[Jimmy9190]

Probably a bad door lock actuator in the driver's door. It is the master for the central locking system. Sounds like the passenger side actuator is on its way out, too.

The actuator is probably an integral part of the entire door latch assembly. I don't know whether you can buy an actuator separately from the whole latch assembly. If not, you might look into leaving the factory actuator in place and just mounting an aftermarket actuator in the door, connecting it to the door lock rod and the 2 wires that went to the original factory actuator.

You can buy aftermarket door lock actuators at Best Buy, Pep Boys or any good car audio/alarm store for about $20.00 each. I just did this same exact thing on my gf's Honda Accord last year. She was having the exact same problem, intermittent keyless and door lock operation, then it quit altogether.

 

[Trav]

Maybe a bad connection or any one of a number of things.
The wiring bundle on the trunk lid hinge is a known problem and causes a whole host of problems,the whole locking system loops through this harness.
Defective/dry actuators and dry lock mechanisms are also common.

You could try resynchronizing the locks,there are a few methods depending on model and year,the workshop manual should have the procedure.

 

[Nick R]

Lock actuator. We had to get the ones in the front (Driver and passenger) done on the expedition a few years back.

 

[bigmike]

Lock actuators can do some weird things when they're on their way out. I had a 94 Accord that would lock intermittently all by itself. Changed the driver's door actuator and problem fixed.