[noah.s]

When I bought my car the lock button on the spare fob didn't work. I could never figure out why and assumed the switch failed.
I used a multimeter to check if the switch worked last month and it did not. No visible damage but it's definitely not working.

So I spent some time finding a replacement micoswitch and figuring out how to replace it. Found a video online of a microswitch replacement on a key fob and it looked easy so I ordered some! I paid like $2.50 on aliexpress for like 10. Shipping took like a month but they arrived today.
So it wasn't as easy as the video. The video showed just touching each of the pads on the switch and it would pull off since the solder melted. Wasn't that easy for me but I got it off. I was afraid I was going to break the fob. I had to pry the switch off with tweezers.

Anyway, putting the new one on was easy. Just align the switch on the leftover solder points, hold down with tweezers, and touch the soldering iron to the new pads for a second or two.

The lock button works now and was a pretty easy replacement (never done anything like this) and cheap.
I've got some extra switches so if anyone needs one just pay shipping and I'll send it your way.

[Rogue-OP]

I had the same problem. Glad you got yours working. Also, you might as well replace all the switches at once if you're in there. I recorded a video but haven't edited and uploaded it yet.

http://www.e90post.com/forums/showthread.php?t=1336096