Parking Aid Malfunction service required sensor error

[ADUK]

See attached image.

This happens nearly every time I turn my ignition on, but not every single time, it is intermittent.
If I turn my ignition on, and the error shows up, if I turn my ignition off then set the alarm and then unset the alarm and turn my ignition back on, sometimes this removes the fault, and the parking sensors work fine.

This is happening more and more and virtually all the time now.

I've wiped and cleaned all the sensors, I assume this could be wiring fault.

Any help or advice on where to start?

[Altransit]

I would check the wires attached to the sensors where they run forward to the parking aid module. The wires can get brittle from exposure to water and dirt, and break internally, causing an intermittent circuit.