Rear parking sensor system failure

[Mozambique]

Hi,
So the rear parking sensor system on my 2010 has totally failed. Put it in reverse and the parking sensor dash button flashes several times and then goes out. No beeping from sensors at back (or front).

Over past 24 months have replaced all four sensors at the back with non-OEM parts. When I replaced the outer two I managed to slice through the wire insulation leading to one sensor. Repaired it and all good for past several months. Gotta say the sensor clip system is a pain to release. Struggled with those on all four sensors.

Has anyone had a similar failure? A new wiring harness is cheap, so probs worth replacing to rule that out. Parking sensor module? I looked at a fuse diagram but cannot see any fuse dedicated to the parking sensors?

Any suggestions appreciated!

 

[Rover Range]

Power is supplied to the Parking assist control module by a FET (transistor) in the front fuse box.
When the parking aid system is active, you should hear a clicking noise from all the sensors. You have to put your ear right up on the sensor.

 

[Mozambique]

All sensors front and back quiet - no clicking. The fact the front ones are dead too makes me wonder if its something More systemic i.e. control module?