[Razza525]

Started having trouble with key fob not operating intermittently :confused so after browsing through the forum I decided it must be a battery problem.
I followed the procedure in the "How to" section, fitted in new battery, superglued back together and headed out to the car with a working key and reprogramming procedure for the key I had just replaced the battery.

As I got to the car I just thought I would give the key a try, (not expecting anything to happen as I had just replaced its battery) Lo and behold the car responded and the doors opened :confused

Ah! I thought the immobiliser probably wont recognise the key if I tried to start the car. Put the key in the ignition and it started :confused :confused

Checked my other key and that still works ok, so to recap I changed the battery in the dodgy fob and it worked first time without having to reprogramme it:thumbsup

Anyone ever had this before?

 

[xXNealXx]

Checked my other key and that still works ok, so to recap I changed the battery in the dodgy fob and it worked first time without having to reprogramme it:thumbsup

That's because the transponder in the key is already coded to your car. I would really question that bit about reprogramming. I've changed the battery in my fob on a couple of occasions and never had to re-code.

 

[Razza525]

Hi Neal
The impression given in the "how to" section suggests that it is necessary to recode the key after the rechargeable battery is replaced, but you are now just confirming what I found today.

When I changed the battery in my focus key fob it needed to be reprogrammed to do anything after the battery change, so I assumed from what I had read on the forum that the BMW would be the same.

 

[xXNealXx]

The transponder code is fixed once programmed. You only need to re-program with a complete new key.

 

[Ronnie]

IIRC if the battery is changed before a certain amount of time elapses then the key keeps the coding