Anyone any idea why my Parking Sensor Display no longer appears? ...

[JulianHicks]

I upgraded my 2005 A8's parking sensor ECU in February to the C revision that shows the display on the MMI screen. It worked fine since then until today, when I noticed that the display no longer appeared whenever I used Reverse gear or pushed the button on the dash

I've scanned the ECU and there's no DTCs and the coding hasn't changed somehow, so I'm puzzled why it no longer works!

Address 76: Park Assist        Labels: 4E0-910-283.lbl
   Part No SW: 4E0 910 283 C    HW: 4E0 919 283 C
   Component: Parkhilfe 8-Kan H12 0030  
   Revision: 00H12000    Serial number: 08720610203793
   Coding: 0301008
   Shop #: WSC 02313 785 00200
   VCID: 234588EDE204395F59-8076

No fault code found.

Anyone have any idea of any tests to try or settings to check please?

Julian