Central Locking and Key Sync/UnSync

Hi Guys,

I have just bought a used E46 - 1998 model.

One of the weird problems I have been facing is that somehow my car keys become 'unsyncd' it means they wont lock or unlock the central locking - but will still operate the ignition. So i can drive the car but cant unlock it (if its locked) - today had to call the ADAC service to unlock the car for me.

And this has happened a couple of times. I solve the problem by pressing the Unlock button + 3 times lock button on the remote to solve the problem - the car unlocks and then locks itself - seemingly signalling a pairing and it works ok. But i dont know why it needs this pairing or syncing after every few days.

Tody i have just left the car on a workshop to sort it out but i just wanted to have your views on this problem. What causes a car key to 'unsync' (apart from battery changes. Remember i had changed the battery one month ago and paired the key. So i know its not the remote battery thats causing the problem.

Any views would be welcome :)

Regards

LEO

Central Locking and Key Sync/UnSync