Hi Guys,
Apologies for not being a big poster on this forum, I'm from the UK X5 forum which is currently broke
You need to get to the microswitch. It's a common fault of the metal lever mechanism on it rubbing free from the plastic holding piece, silly design. The X5drivers.co.uk forum is going to be up soon (we all hope) and I did a write up with pics there.
Best description I can give you is:
1. Get body coloured plastic piece off
2. You'll see a plastic casing next to the motor (but behind the mirror). This slides out and holds your microswitch and the offending lever in place
3. The lever moves down when the mirror is in motion pushing on the sensor - this tells it what position it is in. Your lever is not in place properly and so the push button actuation is not happening correctly, so the mirror springs back out.
4. Be CAREFUL when pulling the plastic housing for the switch out, the metal lever is small and may fall out.
5. The fix is to use a hot gluegun to place it back over the worn away plastic raised locating bit.
Wish I had the other site up - you would be able to see. We have had 3-4 weeks without the site now and it should be back real soon. If you have the patience, keep checking and then do a search for 'sanj' as the author and 'retro fit mirrors' (I think) to get the whole write-up. On that note, hope our original mods get the data back!
Good luck.