Key fob

B300ABT

Member
Whilst continuing my ongoing battle with my immobilised A2 (and thank you so much to the Forum members who have significantly helped me along the way so far), I now have another query.
The key fob on the A2 in question has had a long and hard life, and whilst checking it today against one of my operative ones, I noted that the connector from the PCB to the battery is a bit of a lash up by comparison, and wondered what effect this might be having. I also wondered what the relevance (if any) of X7R being printed on there might be? Are there a limited number of alarm PCBs and this is a means of identifying which one you have?
image.jpeg
 

timmus

A2OC Donor
I've had a bit of a read of your previous posts to get the background on this. From what I can gather, there is perhaps some confusion between the remote central locking, the alarm system and the engine immobiliser. It seems that these systems are sometimes being conflated with each other.

The circuit board shown above is part of the remote central locking system. It has nothing to do with the engine immobiliser. So, a question to help establish what the problem actually is...

Can you turn a key in the ignition and start the engine?

Cheers,

Tom
 
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B300ABT

Member
I understand the confusion Tom, but I'm not conflating the two, although I freely admit that I hadn't realised initially that the alarm and immobiliser functions were entirely separate. The issue with the immobiliser is now sorted out .
I'm just curious as to whether I can get the remote locking/unlocking and alarm system operative again via the key fob, which has been doing a good impression of being totally knackered for a very long time.
 

timmus

A2OC Donor
OK, great stuff!

I don't know what the 'X7R' relates to, but it won't be of any significance. The number that's important is 8Z0 837 231. This number may or may not be followed by a 'D'. The 'D' (or lack thereof) is of vital importance. Any replacement will need programming to the car; each fob transmits a unique signal, and your car would need to be told to respond to that unique signal.

Of course, it could be that the CCCU (which receives the signal from the fob) is the faulty component.

Cheers,

Tom
 

B300ABT

Member
By way of an update.....my bar steward of an immobilised A2 is finally back in action! Engine running, no alarm flashing lights all round, and central locking working perfectly - and all thanks to Sarge on this Forum, to whom I am massively indebted. Great bloke, great Forum......and thanks to all others who gave input.
 
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