Start Stop and key not recognised issue, a6 c7 2013 63

[Recluze]

Hello
My car was water damaged since then I have issue with keys. They always display message
"Keys not recognised, hold back of the keys against marked area"
Second issue is start stop does not work

I have taken the car to Listers Audi and as per their diagnostics no faults found. I am pretty sure it's some module which is not working fully but not showing faults either but does any one knows what modules control them so I can buy n replace this module ?

Thanks

[SlickMachine]

Not to be Captain Obvious here but....have you tried replacing the batteries in key fob?

Sent from my Nexus 6P using Tapatalk

[Recluze]

Yes the batteries have been changed. thats the only thing Audi Suggested and then changed batteries on keys and also reprogrammed them. Audi carried out Deep Diagnostics and nothing came up.

[RAF_S7]

Don't know if this helps you or not....

http://etka.cc/audi/part_single/cata.../274652/lang/e

[sirmium]

Does your passive entry work?
From either side of the car including trunk?

If above answer is yes, I would be checking center console antenna, somewhere below cup holder.

if the answer is no, I would be checking passive entry electronics. For C7 passive entry/start electronics is inside bcm, so might need new BCM.

Sent from my keyfob