2008 X-3 has no automatic fold in button for mirrors. Owners manual makes no reference for how they should be fold it in manually.

[Gregorious]

I’m assuming the wing mirrors should be folded in manually prior to going through a car wash… but verifying that with the Manuel, or on the Internet is impossible.

[Greydog]

Morning Greg 

Welcome to the Forum

The mirrors are ratchet mounted obviously the ratchet is stiff enough to hold the big mirrors steady when the car is travelling at speed. That means if you want to fold them by hand they will take a good shove.

However with my X5 on the rare occasions I use a car wash (mainly winter when I have been off road and the car is muddy) I don't fold the mirrors and have never suffered damage. Mostly it's Bucket and Sponge time.

If your a DIY fan you could pop the rear cover on a mirror if the motors are there (they often are) you may only need a new drivers door master switch with the fold button and maybe a door loom and a fuse. You could then activate your own mirrors. I also have a wiring diagram for Fold on Lock Unfold on Open 

Dave