Rear Parking Sensors (again)

[whammer007]

Hi all,

I posted a while back regarding the rear parking sensors on the wife's B7 Avant, and advice was given about checking for the "ticking" from the sensors when active. I found one sensor was not ticking when active.
I waited until now (as the car is due a service) to mention to the dealer about the fault (which is intermittent) and they were checking it today.
They say there is no fault at present with the system, and that they are happy that it's OK.
I thought VCDS could interrogate the system for previous faults, or is this not possible with the sensors?
I'm beginning to suspect a wiring fault at the rear, does anyone have any likely failure points to check?

Regards,

Colin

[iwaters]

Yes the controller for the parking sensors will record histroical fault codes. Even if there is a fault with the wiring it should show as an error code.

Using VCDS you can view various information regarding the sensors, such as the distance from the object, their oscilation time etc. The oscilation time is an interesting one. One of my sensors doesn't work, but doesn't show a fault code. When viewing the measuring block for oscilation time it is outside the 4m/s the workshop manual says it should be and the sensor should be replaced.

You could ask them to check that but they will probably charge you £90 for a diagnostics.