Since I got my E86, the boot didn't open from pushing in the BMW badge/roundel. It would open from the key fob, so I knew the latch was all OK.
I checked the wiring first, and it was all OK, so I removed the lock itself to see if I could find a cause. There is a microswitch, operated by an arm that is meant to rotate with the badge as it is pushed in. Mine had seized up, and no longer rotated. If I activated the microswitch manually, then the boot released, so I knew the wiring/electronics were all OK.
I don't have pictures of all of the steps as my boot was already stripped bare, but the rough steps are:
- remove the boot plastics - it's only the large panel covering the lock that you need to remove, but it might be clipped under the others (I can't remember). There are some visible screws, and the rest just clips in - it should be fairly obvious.
From now on, we'll be working inside the boot, looking at the lock from behind.
From here, you should be able to just about make out the microswitch in question (it's easier to spot if you look from the left (UK driver's) side of the car. Now, you can press/open the boot lock - and if everything is working, you should see the an arm move and press the microswitch. For the purposes of this guide/fix, hopefully the arm doesn't move! If it doesn't, you should be able to reach in by hand, or with a pick, and press the microswitch manually. If the latch fires, then you know that this is the cause of the problem, and you need to free the arm up.
See the microswitch and arm in the closed position, here:
And how it should look with the boot badge pushed in - notice the arm has moved and is pushing down on the microswitch? At first, mine wasn't moving, and that was the cause of my problem.
To remove the lock:
- unclip the bowden cable from the lock
- remove the boot lock from the car - there is one plug and three T25 screws holding it in
- feed the lock gently out of the boot so it is removed from the car
You can see the arm and the microswitch here, in it's closed state:
And how, with the lock opened, the arm hasn't moved - this was the cause of my problem:
To fix, undo the 5mm allen key, and you should be able to work the arm back and forth/up and down until it comes off the lock. I had to use some penetrating oil (plusgas) and a trim removal tool to gently work/pry the arm from the lock.
Once removed, clean regrease the arm (I used red rubber grease - hopefully not a choice I come to regret!)
Now replace the arm and refit the allen bolt. When refitting the bolt, you cannot do it too tight, as this will cause the lock to bind up and not spring back closed when you let go. As a result, you will need to put some threadlocker on the bolt (as BMW did) to stop it backing out over time.
Once done, you will have an arm that moves freely in line with the boot lock opening/closing!
Refitting is the same as removal, as they say. Hopefully this helps someone else in the future
I checked the wiring first, and it was all OK, so I removed the lock itself to see if I could find a cause. There is a microswitch, operated by an arm that is meant to rotate with the badge as it is pushed in. Mine had seized up, and no longer rotated. If I activated the microswitch manually, then the boot released, so I knew the wiring/electronics were all OK.
I don't have pictures of all of the steps as my boot was already stripped bare, but the rough steps are:
- remove the boot plastics - it's only the large panel covering the lock that you need to remove, but it might be clipped under the others (I can't remember). There are some visible screws, and the rest just clips in - it should be fairly obvious.
From now on, we'll be working inside the boot, looking at the lock from behind.
From here, you should be able to just about make out the microswitch in question (it's easier to spot if you look from the left (UK driver's) side of the car. Now, you can press/open the boot lock - and if everything is working, you should see the an arm move and press the microswitch. For the purposes of this guide/fix, hopefully the arm doesn't move! If it doesn't, you should be able to reach in by hand, or with a pick, and press the microswitch manually. If the latch fires, then you know that this is the cause of the problem, and you need to free the arm up.
See the microswitch and arm in the closed position, here:
And how it should look with the boot badge pushed in - notice the arm has moved and is pushing down on the microswitch? At first, mine wasn't moving, and that was the cause of my problem.
To remove the lock:
- unclip the bowden cable from the lock
- remove the boot lock from the car - there is one plug and three T25 screws holding it in
- feed the lock gently out of the boot so it is removed from the car
You can see the arm and the microswitch here, in it's closed state:
And how, with the lock opened, the arm hasn't moved - this was the cause of my problem:
To fix, undo the 5mm allen key, and you should be able to work the arm back and forth/up and down until it comes off the lock. I had to use some penetrating oil (plusgas) and a trim removal tool to gently work/pry the arm from the lock.
Once removed, clean regrease the arm (I used red rubber grease - hopefully not a choice I come to regret!)
Now replace the arm and refit the allen bolt. When refitting the bolt, you cannot do it too tight, as this will cause the lock to bind up and not spring back closed when you let go. As a result, you will need to put some threadlocker on the bolt (as BMW did) to stop it backing out over time.
Once done, you will have an arm that moves freely in line with the boot lock opening/closing!
Refitting is the same as removal, as they say. Hopefully this helps someone else in the future
