I have had a couple of strange problems and I can't really make sense of it. When I parked the car, I locked the doors as always with the windows closed (I am absolutely sure about this; it was freezing cold outside). When I came back, the car was still locked, but the front windows were down. I immediately checked whether anything was stolen, but that was not the case and there were also no signs of forced entry. When I wanted to start the car, I had a left rear light warning, but all rear lights (brake light and indicators included) still worked perfectly. 5 minutes later, the warning went away, only to come back on when I started the car the next time (it's still active now). Does anyone have any ideas what the problem might be?

Perhaps I should also mention that I have had some 'mild' engine problems with, what I believe to be irregular fuel injection (which I have already addressed by this time and it seems to have helped), but I cannot see how this engine problem could be related to windows coming down on their own and a faulty rear light warning, which is more electronics related.

2 Answers 2


Sounds like a problem with a module. There is a feature in most BMW's that rolls down all the windows when the unlock button is held but if you are sure you didn't do that then it could be a module. (Note: some BMWs relock if no doors are open after a specified time period).

Since you also had incorrect rear light warnings at the same time, I would suggest trying to find if the same module does both and if so replace it.

  • I am aware of that feature. It could have accidentally rolled down my windows while the button was being pressed down in my pocket, but it takes quite a while for both windows to completely go down, so I doubt it, but I can't rule it out. The module that deals with the windows is the GM5 central locking module, but since everything else that module does still works fine, I doubt it's due to that. I haven't had the window problem anymore, so replacing it is probably unnecessary. [...]
    – Ben
    Nov 15, 2013 at 23:46
  • [...] Since the only issue now seems to be the faulty light warning, I think I will just wait for now to avoid unnecessary costs and repairs. In case the window problem or other problems that could be related to the module come back, I can still replace it.
    – Ben
    Nov 15, 2013 at 23:49

BMW bulb holders are well known to overheat and deteriorate from the heat. Remove the bulb holders, one at a time and check for discolouration. Replace them if so.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.