My windows go down and sunroof opens up on their own when the car is just sitting parked and in the off mode. It only happens when it rains. I think that something in the computer gets wet. This is a 1999 bmw 323i. What causes this? How can I stop this from happening? Thanks in advance for your assistance.

Asked by Jun 17, 2007 at 04:23 PM about the 1999 BMW 3 Series 323i Sedan RWD

Question type: Maintenance & Repair

My windows go down and sunroof opens up on their own when the car is just sitting parked and in the off mode. It only happens when it rains. I think that something in the computer gets wet. This is a 1999 bmw 323i. What causes this? How can I stop this from happening? Thanks in advance for your assistance.

24 Answers


its definitely an electrical issue. Probably a case of crossed or exposed wires. There really is no other option but to take it to a dealership and have them fix it.

7 of 7 people found this helpful.

I have been dealing with this problem for 3 months while parked at the train station. Thankfully, it has not happened on a rainy day but it is disconcerting to find the car with four windows and moonroof fully open when I return to the car after riding the evening train. I think I have isolated the problem to the driver's door handle key lock. I sprayed some lock lubricant into the opening to disperse any water that may be causing a short. For now, I remove the central locking fuse #49 and lock the car manually after I park at the train station. I performed overnight tests locking the car in the garage to see if the windows are open in the morning. After a half a dozen tests, the car stayed locked.

15 of 15 people found this helpful.

dont know if youve found an answer yet.. im having the same problem with my 2000 323i.. talked to a guy a while ago and he said its prob the door lock actuator.. for me it only happens when its hot out... anyway. if you hold down the unlock button on the key it sends a signal to the actuator telling it to unlock then roll all the windows down.. its a problem with the actuator... its faulty and thinks its getting that signal.... there have been times where ill walk away after locking it and ill hear it unlock and turn around to c them all opening up.. im still working on finding out more.. if i do and fix it ill post here..

11 of 11 people found this helpful.

and yea i would recommend doing what addict said about the fuse for a temp fix for now

5 of 5 people found this helpful.

Interesting topic, just ran across it. I was thinking it could be the relay that controls the circuit. I know mechanical relays are sensitive to climate changes over time. The spring pre-load gets weak or the contacts (similar to ignition points) get corroded. Sometimes simply taking it out, take the top cover (metal or plastic) off then cleaning the contacts will bring the relay to life. Of course, purchasing a new relay is a better option also.

6 of 6 people found this helpful.

Hey Jace..I have a '99 323i and I was told the same thing (door lock actuator)...after doing some initial research online I was getting scared and I thought it was a faulty General Module but now it looks like it could be this...did you get yours fixed? Did you replace both front door lock actuators or how did you determine which one it was? Thanks in advance!

7 of 7 people found this helpful.

Matt as for the relays. ..I want to see if I could be something as simple as that but when I opened the cover that I just looked completely different to the one you showed and I was confused as to which relay I had to clean exactly... I don't know if you could help me out on this one it would be greatly appreciated!

2 of 2 people found this helpful.

This was just an example (relay panel in a 96 Mercedes C280) All relay or typically the same just located in different areas for different cars I know BMW usually have a covered box in the engine bay that has a clamp or lever that holds the cover down of course there are more relays and fuses under the rear seat for other circuits

5 of 5 people found this helpful.

water is getting in the switch in drivers door thats attached to the lock if you hold the key in lock position and windows are down they will close and so will sunroof, if you hold in unlock position with windows closed the lot will open. rip the door panel off and check the switch thats next to the lock

8 of 8 people found this helpful.

there is no relays or anything under the bonnet that control windows or locking, the control box is behind the glovebox although you could have a leaking windscreen and waters dripping onto it but that very unlikely check the doors its comon that the micro switches play up

2 of 2 people found this helpful.

I dont know what shape u have because your car is the time change for the E46 if its an earlier E36 car like the 1 in the picture, there is a switch on the door catch that over time wears down this can play around with the full closure locking if its really worn the interior light wont go out when the door is closed but have a look I had it on mine and I stuck a small bit of rubber on the end to make the door push it in further and everything was fine, my window would drop a quarter way down and it wouldnt seal when the door shut.

2 of 2 people found this helpful.

LOL yea I have dealt with E21, E28, E30, E32, and E34 but not with an E36.... And MBZ W124, W201, W202, W210 chassis models.

1 of 1 people found this helpful.

just happened to my 2003 330XI. Worth noting my auto key lock's been failing for 2 weeks now-started in extreme cold. Works on rare occassions but usually have to unlock manually

3 of 3 people found this helpful.

Wow, thanks for details. This just happened (sometime before) this morning when we walked out wondering if we had a poltergeist! Called the BMW remote team & HQ, both had no idea, nor did dealer. Much relieved.

3 of 3 people found this helpful.

Just happened with my x3 and now its raining buckets outside. Gonna try that key lock stuff as soon as it stops. Even tthough the battery is going out in the key also. Never knew these bmws would be so tricky.


I found a very easy and effective solution for sitting on my key fob and opening my car's windows by accident. I bought a leather key fob pouch through Then I glued one of my pet's old aluminum dog tag inside the leather cover so that the tag covers the buttons on the key fob. I used a hammer to beat the dog tag into a curved shape approximating the curve of the leather cover. I then used a leather/metal glue to affix the do tag to the inside of the leather cover. If you know how to sew leather you could stitch another piece of leather around the dog tag so that it can't possibly pull away from the leather key fob cover. I hope this helps.

1 of 1 people found this helpful.

This just happend to my 07 328xi and it was raining but what do you mean when you say it's in off mode

4 of 4 people found this helpful.

I'm not sure what causes it and not sure what the definitive solution is but I do have a fix. It's a simple fix and will be temporary until it goes into that mode again, but just disconnect the positive cable on your battery for 30 seconds and it will reset whatever is causing the windows to deploy. Last time I did that it lasted almost a year. Hope that works for others with this irritating problem.

5 of 5 people found this helpful.

i have an '08 528i, wife went to run errands and each time she came out from a store the driver side passenger window would be down.

1 of 1 people found this helpful.

BMW is not the only one. It also happens to our '07 Lexus IS250, very sporadically. But (to date) always in our garage. Not outside. Not correlating with rain (or any other event I can think of).

1 of 1 people found this helpful.

I have a 2003 BMW 530i. Just started to have this problem yesterday. Car parked and locked. After perhaps 10 mins or so, the car unlocks, all windows an sunroof roll open ?? Have tried clearing with the internal BMW transmitter - holding positions 1&3 down but the light does not flash. Now I'm stuck. Any ideas ?


For all that are experiencing this problem, check out this link before you start pulling things apart. You don't want to sit on your fob! t=437009

1 of 1 people found this helpful.

HELP!! The same thing is happening to my BMW 325i 2003.. but this happened after I got a replacement key... right after i close my door my windows go down after a few minutes.. normally this is happening while it's hot outside.. sometime when it's raining... any suggestion??? Don't want to take it to the dealer when they going to charge me out the a**!! When it's something simple.. please help!!

1 of 1 people found this helpful.

I have a 2002 525i where the windows will roll down and the sunroof will open upon locking the car. The key fob doesn't work and has no battery so there is no issue with hitting the button by accident while in a pocket. It happens only when I lock the car. It doesn't matter if i quickly turn the key or hold the key in the lock position, the windows and sunroof will always open; this is counter productive to locking the car, for sure... I'm thinking that the actuator might be jacked up in the door or the convenience feature is not working as it should. After looking through the postings, there isn't anything that resembles what I have going on, however, there was one post that referred to "when it rains", which might be revealing as the water might be getting into the door lock and shorting it to complete the circuit as if the key were inserted somehow.......

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