I posted this on your fellow E39 forums to no avail. This is really a weird one. My car has auto locks enabled. Pulled out and drove abt. 5 miles and out of no where the passenger side lock starts going up and re-locking by itself. At the same time, it sounds like a motor slipping like what you used to hear just before your electric antenna would go out in years past on American cars. sounds like plastic teeth slipping/grinding/broken; motor/gears slipping and "whirring". At first it was a slow whrring and the lock would go up and down. Then it got much faster and lock stopped moving. then lock button quit moving, but whirring kept on-- on passenger's side. Immediately after, the driver side starts same behavior except after the lock went up and down a couple times and the whirring kept going and getting faster (like whatever teeth were left were now broken) the lock itself stopped actuating, but the whirring just stayed on. Now, it sounds like both sides are staying on and whirring/grinding/drone is coming from both sides of the car and is now hard to pinpoint exactly where noise is coming from. With sound hitting both ears now, it begins to seem like it is coming from console or dash area. Turning car off does nothing. Turned around and headed home after punching the center lock button few times to no avail.
I am now heading home and grinding is still happening. It must have been about 5 minutes by this time that the lock actuators (I'm guessing) are both growling away. I go to lower the driver's side window on the trip home and at last the sound stops (as soon as I go to lower the window). Get home w/o further incident, but when I push the center console lock button, the rear door locks act completely normal, but front locks make same whirring noise for about 2-3 seconds each and then stop. Front doors do not lock. I can push the front lock buttons down by hand easily and by pulling the door handles, the locks will pop up just fine. Pushing center lock button just produces a 2 second whine from each lock area and only rears will actuate.
Don't understand the sequence of how the problem started. Passenger side starts by itself...locks and unlocks a couple times and then whirring starts. Problem jumps to driver's side now in addition to passenger side and it locks and unlocks a couple times and then joins in perfect harmony with the orchestra on the pass. side! Using remote produces same 2 second whine, but if you push unlock on remote it will only try once and then you must push lock on remote next. If you push lock on remote or unlock on remote multiple times in a row, it will only whirr once. You must maintain sequence of lock/unlock/lock with the buttons as if the car believes it has locked and will only respond to the unlock command next. Help!
I am now heading home and grinding is still happening. It must have been about 5 minutes by this time that the lock actuators (I'm guessing) are both growling away. I go to lower the driver's side window on the trip home and at last the sound stops (as soon as I go to lower the window). Get home w/o further incident, but when I push the center console lock button, the rear door locks act completely normal, but front locks make same whirring noise for about 2-3 seconds each and then stop. Front doors do not lock. I can push the front lock buttons down by hand easily and by pulling the door handles, the locks will pop up just fine. Pushing center lock button just produces a 2 second whine from each lock area and only rears will actuate.
Don't understand the sequence of how the problem started. Passenger side starts by itself...locks and unlocks a couple times and then whirring starts. Problem jumps to driver's side now in addition to passenger side and it locks and unlocks a couple times and then joins in perfect harmony with the orchestra on the pass. side! Using remote produces same 2 second whine, but if you push unlock on remote it will only try once and then you must push lock on remote next. If you push lock on remote or unlock on remote multiple times in a row, it will only whirr once. You must maintain sequence of lock/unlock/lock with the buttons as if the car believes it has locked and will only respond to the unlock command next. Help!