DIY - Keyfob repair [Archive] - Bimmerfest - BMW Forums

: DIY - Keyfob repair

08-30-2010, 01:21 PM
Hi All,
I had a problem with my spare keyfob not working. it would open the doors but not lock them. I know that this is a symptom of a flat battery in the fob and you need to put it in the car to charge up.

Well I had it in the car for approx 5 hours and it made no difference.
I thought it must be the battery that's dead. therefore open it up and replace the rechargeable battery...

so here goes.

Cut around the key with a sharp craft knife. (this took about 10-15 mins)
By richpu ( at 2010-08-30

Once I cut around the keyfob case and opened it up, it became clear why the locking was not working. The switch had come unsoldered.

detail of the rechargeable battery

Re-soldered the switch and tested it and the car locked and unlocked just fine.
so that saved me having a mess around with the battery.:)

Once I was happy it was working I glued and held it together using cable ties until the glue dried.

Hopes this helps anyone if they have the same issue.