Hi, I recently bought a 2006 R53 with two original 3 button dead key fobs. After much reading I ordered and replaced the rechargeable batteries inside both.
One of them now successfully remotely unlocks the car and the boot but does not lock (middle round button). The other key is still dead (batteries are charged and all tiny buttons on the circuit board work OK in both keys).
I've tried multiple times all reprogramming/registering techniques from many many posts and videos about the subject with both keys with no success.

Could it be that the registering feature in my car is disabled? I can't think of any other explanation.

Thank you.

 

I answer to my own post so I can help anyone having a similar issue. After scanning, I found out my car was showing a couple of non related ECU errors (transmission, e-fan, etc). Once I could fix and clear those errors, I could succesfully re-register the key fobs and now they lock and unlock as they are supossed to.

 

Congrats and welcome to the forum!

 

Totally-intuitive solution likely covered somewhere in dealer-only repair instructions we're not allowed to have because BMW.

 

@Daftlad That phrase should be attached to your signature.