boot opens by itself when driving !

[mel_2013]

hi need some help guys ! My 2011 z4 has decided that it would be great to open the boot by itself when i go to move off ! there is also two led lights constantly lit on the strip light across the boot lid, oh and the boot will not open manually only by using the key fob ! any ideas?

 

[Maniac]

Sounds like you have water in the electrics/a short somewhere. DIY take out linings and check or take it to a garage for checks.

 

[mel_2013]

Thank you ! Am going to take it to my local garage in the morning , hate it when things like this happen. :headbang:

 

[flybobbie]

Like suggested could be water. I recently had the inside boot liner off. The wires for the boot release micro switch and the led high level lamp are harnessed together just under the boot. Have a look to see if the trim is damp around the warn triangle holder.
Water always drains from the high level area when I lift the boot when it's wet.

The boot release has a micro switch that operates a solenoid, so that possibly stopped working, but the remote operates the same solenoid. If the damp shorts the micro switch, the boot could open itself. Especially recently if salty water has got in.

 

[mel_2013]

Thanks for your help ! I will pass this message onto the garage to help them ! I would go check what you have said but here in Cornwall it has not stopped raining all day !

Will post an update tomorrow after I get the car back , hopefully it won't have to go to oceans

 

[flybobbie]

Look here at the wiring diagram.
Shows micro switch attached to the emblem badge boot release.
http://www.z4-forum.com/forum/viewtopic.php?f=45&t=91766

Bottom right trunk lid button. (Ignore the squiggly red line).

 

[mel_2013]

Well I've got the car back today and they couldnt find out what was causing it , they have disconnected the brake light and that seems to have stopped the problem . Have booked it in to BMW .... lets await the bill :thumbsdown:

 

[Bb5061]

Hi, what happened in the end with this? I'm having exactly the same problem with my Z4, and I am dreading what it's about to cost me.

 

[StuartH]

Same problem started on mine this morning. Any solutions or idea of repair cost ?

 

[Pauly]

Last two nights leaving work, I've had to jump out and close the boot. Just checked tonight and noticed my rear top break light is constantly on (but faint) when I move the boot BMW roundel that light goes off, just stuffed a small micro fibre cloth in the space so the battery doesn't run flat. Think this is linked to flybobbie posts as this mechanism seems to control a number of functions. Better learn how to use a soldering iron.

 

[Pauly]

Little update, followed flybobbie's post took the assembly out and turns out the wires are fine, no shorts! So I'm left scratching my head now. Basically when I press the break pedal the boot opens, disconnected the top break light and it still does the same, funny enough my rear lights are on without the switch being turned. May have to remove the rear lights to investigate in there. Please if anyone has any other thoughts let me know. Cheers

 

[Pauly]

Sorry me again anyway removed one of my rear lights due to water ingress and whist removing the light discovered a little pool of water beneath the little storage box. Cleaned it all out and fitted a new lamp and guess what, the boot still fuckin opens when I press the brake haha. I have disconnected the top break light as it activates the boot latch, but even if I leave it disconnected, pressing the brake still opens the boot. Any guesses welcome

 

[Pauly]

Forgot to add chucked a multi metre on the battery and it's running over 14 volts :roll:

 

[Pauly]

Like suggested could be water. I recently had the inside boot liner off. The wires for the boot release micro switch and the led high level lamp are harnessed together just under the boot. Have a look to see if the trim is damp around the warn triangle holder.
Water always drains from the high level area when I lift the boot when it's wet.

The boot release has a micro switch that operates a solenoid, so that possibly stopped working, but the remote operates the same solenoid. If the damp shorts the micro switch, the boot could open itself. Especially recently if salty water has got in.

Flybobbie where is the location of that micro switch (is it attached to the back of the BMW emblem) or is it the two that are part of the assembly attached to the inner boot lid, the ones that you fixed as the wires snapped. Cheers

 

[flybobbie]

Back of the emblem.

 

[Pauly]

Back of the emblem.

Cheers, much appreciated

 

[RobbiZ4]

 

[Pauly]

Cheers RobbiZ4
I will explore your advice this weekend, when I have time to remove all of the trim from the boot, cheers for the post

 

[RobbiZ4]

I have disconnected the top break light as it activates the boot latch, but even if I leave it disconnected, pressing the brake still opens the boot.

Could you please explain a bit more or better with a photo, what has been disconnected?

 

[Pauly]

Followed your advise RobbiZ4 and this what my connectors looked like when removed