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Discussion Starter #1
I have read threads about people not able to open their trunks, but this is something different.

If I pop my trunk (doesn't matter if it's with the fob, dash button or trunk button) the trunk pops properly, then I open the trunk, do whatever task I needed to do, then I go to close the trunk.

Here is where the problem arises. Just before the trunk closes the latch makes its open noise again and the trunk won't latch, I lift it up an inch or so it resets, then I go to close it and opens again. Sometimes this happens twice other times over 30. Right now my trunk is open in the parking lot because I was so sick of it.

Once I do finally get it closed and latched it stays that way and never randomly opens or pops.

What might be wrong? My thoughts were a faulty latch, but I'm not sure whats triggering it or one or more of the wires in the trunk harness thing have rubbed through.

I have sort of eliminated one of the switches being bad since it seems to do it regardless of the switch I use to pop the trunk, and I would think that if a switch was making contact, the trunk would randomly pop.

Any thoughts are appreciated. Such a little thing brings great irritation.

Thanks.

Bob
 

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That's a heck of an interesting problem.

I can think of only 3 possible solutions:
1. You are holding the key in your hand and pressing the trunk button while trying to close the trunk. this seems unlikely, but would cause the issue :)
2. You have a wiring short, probably in the area where the wires pass from the trunk lid to the body,
3. The brain in your central locking module has come in contact with HAL2000 and no longer likes you -- or is failing...

My money is on #2.

d-
 

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Discussion Starter #3
Well, I'll have to pull apart that whip and see whats in there.

I hate electrical gremlins.

Thanks.

Bob
 

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Electrical release is in the trunk lid. Remove the 2 "push pins", the vanity cover (little rectangular piece), and the screw under the vanity cover to get the trim off.

You should see the latch (1 piece) and the operating bar attached to it...

d-
 

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Discussion Starter #6
I took the loom apart whare it goes from the trunklid to the chassis and there were several frayed and shorting wires.

I would guess your problem is there too.
 

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Discussion Starter #8 (Edited)
I used split heat shrink tubes and 1 at a time covered them up, then I wrapped the whole bundle in tape.

One was particularily bad so I curt the section out and soldered in a new piece.

Bob


PS, I didn't realize how old this thread was, i forget I've had my M5 this long (got it oct 07). It is by far the best and most favorite car I've ever owned. Makes me smile everytime see it hibernating in the shop area.

----Edit ---

Hahah, I was typing that PS before or rather during you editing your responce. How funny.
 

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yes....that is definitely the problem. You just cut open the rubber tubing, or is there a way to get it off?

P.S. for those with this problem, I found a temporary fix - lock the doors before closing the trunk, the release does not activate when the doors are locked, so the trunk will close.
 

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Discussion Starter #10
No! Do not cut open the rubber thing. I had to go look how I did it. Just grab the rubber where it meets the lid and pull, kind of wiggle back and forth and it will pullfree of the trunk. Then take and slide/fold down on itself (like a tubesock, or uhm, the other rubber thing guys use...) to expose the wires. The frays should be nearer to the lid.

Bob
 

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I used split heat shrink tubes and 1 at a time covered them up, then I wrapped the whole bundle in tape.
...
I know what heat shrink tubing is, and I know what split loom is - is there actually something called split heat shrink tubing or is that just a word out of place?

d-
 

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Discussion Starter #12
No, I just split regular heat shrink tubing so I didn't have to cut the wires, pinched it closed and when I heat it up with the heat gun, it melts back together.
 

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I am having trouble removing the tubing...I was able to pop it off of the trunk but can't pull it down more than an inch or two and then it seems to get "stuck" on something. I don't want to pull on the rubber cover too hard for fear of ripping one of the wires out....do you have any tips on getting the tubing to expose all of the frays?
 

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Discussion Starter #14
I just kind of worked it down, it's a pain. As soon as I could I grabbed the bunch of wires with my fingers to stop them from pulling and rubbing. You can pull the other end off too, if it will help at all.

All my frays were right at the trunk lid.

Otherwise the next step would be to take off the trunk panel and take lossen the whole harness. I didn't have to go to that step.

Bob
 

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Baddd news:

pulled the rubber down more to reveal a MESS, bunch of previous owner tape, many badly frayed wires and 3-4 of the wires snapped off completely....any advice very much needed
 

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This is frustrating, what it boils down too is a few frayed wires in my trunk are stopping me from using my entire car. Is there any way I can unplug this wire group completely and not have electrical loss, then have someone repair the wires? I don't want to have to get my car towed to a repair shop to fix something as small as frayed wires.
 

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That's the problem with cars - the whole thing is a ground, so any bare power wire will cause you huge problems.

**Nevermind - plate light goes directly to LCM** Items like a trunk or a door usually have a Molex connector. This is basically a connector that is designed to flex and take the constant abuse associated with opening and closing. The nice thing about these connectors is that they have a plug on each side (to allow the molex to be replaced instead of having to run an entirely new harness. Look on the trunk side where the wire comes through and see what you can find. You obviously won't be able to disconnect it lid side, but you should be able to get to it on the trunk by removing the trunk lid liner (and possibly one side liner as well). **No such luck**

The other option is to pull all the fuses related to that part of the car. This likely would include your power door locks and rear lights. If you are lucky, the plate light is on a separate circuit from the taillights, but I wouldn't hold your breathe.

d-
 

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Doug, thanks for the response.

the damaged wiring goes through the rear firewall and not sure where after that. Who knows where the molex connection is?

I am going to try and pull some of the fuses and see if I can get these wires to become powerless.
 

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Doug, Got my car powered up....is there any fear of pulling potential fuses? Can I hurt anything?

After removing fuse #4 - trunk lighting, the license plate light is still on (which is powered by my damaged wires.


Looks like I may be unplugging the battery at work tomorrow......


P.S. by firewall, I meant the car's body...it enters a sealed passage into the cars cabin which would open a whole new can of worms.
 
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