In my expirence it's usually just the wire braking from all the bending over time on OEM sensors. I just cut out the middle of cable and replace with bendy microphone cable. Couple of times that I have tried aftermarket sensors they only last 1-2 years and usually the sensor itself fails.

Okay, I think I found an answer – Wabco is the original supplier. Thanks to eBay.de and Google image search! Buying Wabco instead of original part (obviously also Wabco) saves around 66 €. This I can accept.

Found also some good info from AudiWorld and Audipages

https://www.audiworld.com/forums/a8-...ative-2841023/

http://www.audipages.com/Tech_Articl...eshooting.html

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