Bought a used 1 Series interior rear view mirror from ebay to do a clown nose transplant (including LED) as my mirror has a gaping hole underneath. The donor mirror was only £10 so can't complain.
Took the donor mirror apart just fine, removed the LED board and de-soldered the LED without any problems. My issue was while soldering the LED into my current interior mirror. The solder just wouldn't stick to the terminals on the board (even after extensive cleaning). Once I finally managed to get it somewhat soldered, the LED wouldn't work when I fitted it back on the car.
Thankfully there are no problems with locking and arming/disarming the alarm, and now the interior mirror looks like it should with the clown nose on. I can live without a blinking LED.
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