Had a duff rear sensor so replaced it. With ignition on and parking button pressed all seems fine. All reading the same on IIDTool. As soon as I turn engine on the two right rear ones constant bleep and their readings go to 25/30 on the live values on the tool.

I’ve contact sprayed the sensor connectors and main connector in body hollow.

Also substituted another parking ecu but same issue.

It feels like an odd Earth issue but I can really see where or why it’s fine without engine running and as soon as engine starts it goes haywire.

Any advice on where to start?