Boot soft close failure-Fixed

[Ian_C]

Spent a couple of hours addressing this today. First off I checked the boot light connector. 12v present but no continuity to earth - very likely the left-hand soft close loom identified by others on this thread. Stripped the boot lid down, stripped the insulation back and...bingo!

Black wire was broken, green came apart with the lightest of touches, blue was good albeit exposed:


Right-hand loom didn't have any broken wires (yet) but was deteriorating:


Soldered up the left-hand wires, insulated with heat shrink and relooomed with fabric tape:


On the right-hand side I just insulated the exposed wire with electrical tape and reloomed:


Put it all back together, worked a treat

Took a couple of videos from inside the boot of each latch - you can see how the loom moves when the boot opens or closes.
LH latch:
z4 boot left by Ian Conuel, on Flickr
RH latch:
IMG_1265 by Ian Conuel, on Flickr

Fingers crossed that my repair lasts

Have to say what a great resource this thread (and forum) has been. Would have taken quite a lot longer to trace that without the help of fellow owners

[B21]

Well documented write up

[Chippie]

Well documented write up

Agreed
Saved the thread for future reference

[RobbiZ4]

Perfect!

After renovation of the wires, i always secure the strain relief with fabric tape and cable ties like on the following pic:

20211101_E89-Lock.jpg (29.27 KiB) Viewed 1600 times

[B21]

Perfect!

After renovation of the wires, i always secure the strain relief with fabric tape and cable ties like on the following pic:

20211101_E89-Lock.jpg

[DaytonZ4]

I'm not sure if this is related but when we bought our car, I never noticed or realized there's a "soft close" function where you lower the lid and it slowly pulls closed and then locks. But I saw a video recently where the person mentioned this feature existed in the E89. My trunk closes and locks (I can hear something in there doing stuff) just fine. I can press the trunk open (fob, in the car, or emblem) and it unlocks like it should. I have no warning lights. When it unlocks, I reach under the lip and lift it open. Then I pull down and let it drop to close it, and it locks like it should. The whole episode is not any different than my Ford Fusion other than it is obviously an electric/motorized lock mechanism (the Ford is just a spring-loaded catch with a motorized release).

So, did all E89s have the soft close function and if so, could it be the wires people are mentioning on this thread? To be clear, my trunk locks and unlocks fine, it just doesn't do the soft close thing.


TIA, Chunks

[RobbiZ4]

So, did all E89s have the soft close function...

Simply YES, without any doubt. As well as all E93 and F33 convertibles.

[Newzedhed10]

Hey,

Firstly, thank you this forum is an amazing resource.

I have experienced the boot soft close failure on a trip to France... is it normal that the boot locks but appears slightly open
Please can someone talk me through the tools required to fix this (solder iron, heat shrink + tubing, wire stripper, flat head screw driver to pop the liner retainers, and a torx screwdriver set)
And the initial steps of the repair? Are you disconnecting the battery?!

I've tried the local garages but they won't touch a BMW, and the dealer is booked out.

Thanks,

[Nizzy]

Another thank you to the forum and those member who impart their knowledge.

Had this fault occur today! Boot unlocked warning light and gong sounding and boot motor running continously. Thankfully ISearched this forum this afternoon and followed advice. Problem was blue wire had sheared on nearside switch. Other two wires insulation was cut showing bare wire.Wire Soldered and extra insulation placed at plastic clamps. Boot lock and soft close working perfectly. Job done!

Well pleased. Time for tea and medals! Lol.

[MY_Z4_E89]

Hi All,
Just wanted to post and share i had a similar issue with E89 Z4. I finally got the courage and took the assembly apart and found two broken wires on both side of the with microswitches. I want to thank your your support on this issue as you helped me out to root cause the issue. Many thanks.

MY_Z4_E89

[stannie203]

Hi all,

I also have had this fault occur on my 2011 e89 Z4. Two severed wires (green and black). As per the above, without this forum I'd a) have zero clue where to start in finding the fault, b) would be shelling out £400 for a replacement unit and incurring the wrath of my wife for 'buying a heap of junk'.

I took the route of grafting in a new section of wire to bridge the cut. Soldered, heat shrink tubed and then taped for a bit of extra protection. Job's a good'un.