Both front windows randomly going down an inch and then back up

[SimonJohnson]

Both front windows randomly and repeatedly drop an inch and then go back up as if the door handles were being opened and closed. This behaviour starts when I unlock the car with the remote control and continues until I've run the engine for a minute or two. Sometimes the windows also fail to drop when the door handles are pulled. I can't work out what is causing this problem. It's as if there's a control module that isn't functioning correctly. If it was just one window that had the problem I might suspect a door handle switch but it's both of them. If I just unlock the car and don't open either door the windows jump up and down for several minutes until I eventually decide that I have to do something about it and the only solution I've found is to run the engine. I've noticed that the problem is much worse on a cold morning.

Has anyone else had this problem?

 

[firebobby]

Both front windows randomly and repeatedly drop an inch and then go back up as if the door handles were being opened and closed. This behaviour starts when I unlock the car with the remote control and continues until I've run the engine for a minute or two. Sometimes the windows also fail to drop when the door handles are pulled. I can't work out what is causing this problem. It's as if there's a control module that isn't functioning correctly. If it was just one window that had the problem I might suspect a door handle switch but it's both of them. If I just unlock the car and don't open either door the windows jump up and down for several minutes until I eventually decide that I have to do something about it and the only solution I've found is to run the engine. I've noticed that the problem is much worse on a cold morning.

Has anyone else had this problem?

Hello to you too oke:

 

[flybobbie]

I had a problem with my windows and discovered it was a poorly fitting connector on the drivers door window switches.
Became worse as winter arrived.
Took apart and unplugged, clean with contact cleaner and reassemble.
Hard bit was unplugging, as it wasn't obvious how it detached and for that matter how it gave a problem.
But once reassembled it worked fine.

http://www.z4-forum.com/forum/viewtopic.php?f=45&t=72772&p=1067571&hilit=door+switches#p1067571

 

[Maniac]

Poor battery charge leading to malfunctions?

 

[TopDMC]

Poor battery charge leading to malfunctions?

+1
Maniac mentioned this to me a couple of years ago and after an overnight charge never had the problem.

BTW
Welcome

 

[SimonJohnson]

I had a problem with my windows and discovered it was a poorly fitting connector on the drivers door window switches.
Became worse as winter arrived.
Took apart and unplugged, clean with contact cleaner and reassemble.
Hard bit was unplugging, as it wasn't obvious how it detached and for that matter how it gave a problem.
But once reassembled it worked fine.

http://www.z4-forum.com/forum/viewtopic.php?f=45&t=72772&p=1067571&hilit=door+switches#p1067571

Thanks for that idea. I think that my fault is different from that though. The window switches work perfectly. Good that you solved your problem so well though.

 

[srhutch]

I'd be looking at the battery as suggested above.

 

[SimonJohnson]

Poor battery charge leading to malfunctions?

+1
Maniac mentioned this to me a couple of years ago and after an overnight charge never had the problem.

BTW
Welcome

Thanks for your thoughts on this. You may be right about the battery voltage because it's worse on a cold morning and the problem goes away when the engine has been running for a few minutes (except for the occasional failure of the passenger window to drop when the door opens but that could be a separate fault). However the thing that I find surprising about the battery voltage idea is that the car starts perfectly with no signs of a weak battery so the voltage must be very close to the correct value. I suppose I could do a test whereby I leave the battery on charge overnight and unlock the car in the morning without disconnecting the charger. That would be a definitive test. If the windows don't do their merry dance then that shows that a higher voltage solves the problem but if that is the case then there must be a fault with an electronic module somewhere because surely the car shouldn't have this fault simply because the outside temperature is a bit low. Anyway I'll do the test with the charger and post the result in a few days time.

 

[SimonJohnson]

I'd be looking at the battery as suggested above.

Thanks srhutch. I'll do a test with a battery charger overnight as outlined in my reply to TopDMC above. However the car starts really well so there can't be much wrong with the battery but perhaps an electronic module somewhere is on the point of failing and has become over sensitive to slight voltage level changes? I'll post again after I've done the overnight test. I can't be the only E89 owner who's struggling to get to the bottom of this problem. By the way, I love this car, it's just so enjoyable to drive!

 

[SimonJohnson]

Both front windows randomly and repeatedly drop an inch and then go back up as if the door handles were being opened and closed. This behaviour starts when I unlock the car with the remote control and continues until I've run the engine for a minute or two. Sometimes the windows also fail to drop when the door handles are pulled. I can't work out what is causing this problem. It's as if there's a control module that isn't functioning correctly. If it was just one window that had the problem I might suspect a door handle switch but it's both of them. If I just unlock the car and don't open either door the windows jump up and down for several minutes until I eventually decide that I have to do something about it and the only solution I've found is to run the engine. I've noticed that the problem is much worse on a cold morning.

Has anyone else had this problem?

Hello to you too oke:

Hello firebobby, I've not used a forum before so perhaps my procedure isn't very good. Anyway, this forum certainly seems to be useful and very active. Nice to have so many replies so quickly.

 

[firebobby]

Both front windows randomly and repeatedly drop an inch and then go back up as if the door handles were being opened and closed. This behaviour starts when I unlock the car with the remote control and continues until I've run the engine for a minute or two. Sometimes the windows also fail to drop when the door handles are pulled. I can't work out what is causing this problem. It's as if there's a control module that isn't functioning correctly. If it was just one window that had the problem I might suspect a door handle switch but it's both of them. If I just unlock the car and don't open either door the windows jump up and down for several minutes until I eventually decide that I have to do something about it and the only solution I've found is to run the engine. I've noticed that the problem is much worse on a cold morning.

Has anyone else had this problem?

Hello to you too oke:

Hello firebobby, I've not used a forum before so perhaps my procedure isn't very good. Anyway, this forum certainly seems to be useful and very active. Nice to have so many replies so quickly.

Hello again, it's just polite to introduce yourself and say hello in your first posting. I'm surprised more members didn't comment on this too. I'm sure you will find all the info and more on the forum, we like lots of photos of your pride and joy

 

[SimonJohnson]

I've fitted a new battery from BMW and driven the car around to make sure the voltage is completely up. It's made no difference! Exactly the same problem with the windows continually going down and up by about 5 cm in a random fashion until the engine has been running for about fifteen seconds. I'm beginning to suspect the footwell module but that's very expensive and apparently needs re-programming by a dealer once it's been installed.

 

[flybobbie]

I know it's a bit cold to do, but do they go up/down with the roof down.

I found it interesting watching this video
https://www.youtube.com/watch?v=TJ3FkjeL9TE
the measurements taken to set glass height.
Wondered if there is an anti trap mechanism and your glass is rising to high and that is being triggered.
After the car warms up a touch the roof might move up slightly or just the motion of the car moving.

 

[paulgs1000]

Simon, just a thought;

Do a search about re-setting the windows. I remember hearing that this can be done on the Zed using a combination of the ignition and buttons. . . . . . anyone know about this?

Not sure if it would help but why not give it a try?

 

[srhutch]

I've fitted a new battery from BMW and driven the car around to make sure the voltage is completely up. It's made no difference! Exactly the same problem with the windows continually going down and up by about 5 cm in a random fashion until the engine has been running for about fifteen seconds. I'm beginning to suspect the footwell module but that's very expensive and apparently needs re-programming by a dealer once it's been installed.

Do you mean the GM5 module?

If do I would look at sending it away for repair. Much cheaper and no coding required.

 

[Maniac]

All that's needed to set windows up is ignition on then hold down buttons for several seconds after they've gone down completely then pull buttons up and hold for several seconds after they've gone completely up.

 

[SimonJohnson]

I think that the E85 has a GM5 module but the E89 (i.e. my car) has a footwell module otherwise known as the FRM instead of the GM5 and I'm wondering if it might be the FRM that's causing my problem but I'm really not sure.