Stagea radar sensor failure

I drive a Stagea, and what you're describing sounds familiar. An error message in the speedometer and subsequent failures? When did this issue start? Was it after any specific event, like heavy rain or off-roading? Any detail you can provide will be valuable.

It started gradually, maybe a week or two after a long drive on some dusty roads. Then the errors became more frequent. Can I fix this myself, or should I take it to a workshop?

Given that it began after dusty conditions, it may just be the sensor. However, considering the cascade of errors, I'm not experienced enough to provide a solution. To avoid damaging the sensor, take it to a reputable workshop. If it is just the sensor, you're lucky!

It was indeed the radar sensor, covered in muck. A quick clean and calibration at the workshop, and everything is working. Cost me 45€.