I just bought a 2003 316 and one key lets me in, and lets me turn the ignition on, but doesn't start the car, wheras the other is fine.
I assume the transponder that disables the imobiliser is not working in that key. As far as I can tell, reprogramming by holding down unlock and pressing lock 3 times only affects the remote unlocking mechanism, not the transponder/immobiliser mechanism.
Is there any way of getting the immobiliser to accept this key ? Can I do it ? Can a garage do it ? Or do I need to get a new key from BMW for this ?
Thanks for your help,