I have 2010 Superb Estate that has a Brink Detachable Tow Bar with Brink 13 Pin electrics.

 

Ever since the tow bar has been fitted, one of the front sensors occasionally plays up and thinks that something is really close but it's always been a once in a blue moon thing. Recently, when the sensors engage I get a high pitched beep and a warning on the Columbus unit saying that the parking system is unavailable, I've got a Foxwell NT520 Pro scanner that isn't picking up any faults.

 

I don't want to start throwing parts at it but I'm a bit stuck.

@chris-t

You will need it scanned with VCDS to get the codes from sensors

You can try and see if anybody local can help you out

Had a similar issue, open earth to one of your sensors. Somewhere there's a break. I didn't have any codes either.

Put your ear close to the sensors and check whether you can hear a subtle noise. It might give you a clue if you do not have other diagnostic tools.