I've got the PDC display to work on my E53 X5 The problem was I was testing it by putting the car into reverse without the engine running. Although the PDC sensors beep correctly and the reverse camera is shown on the display the PDC dispaly on the Dynavin shows nothing. However with the engine running it all works perfectly.

The only thing I might change is that currently I activate the head unit from the reversing light output on the Light Module Controller (X38 connector pin 9 or 10). It would be better to use the PDC light output since PDC is engaged in both forward and reverse gears when parking (X38 connector pin 1). Currently the Dynavin screen switches off when I put it into drive.