California Rear Parking Sensor

so my California is showing rear left parking sensor , so i scanned it and it showed it was bad , so i bought some replacements from a couple of places one been euro spares and another off ebay both used , i fitted both of them to try both and i got the error still , i did put a meter on the plug and there is voltage there so am guessing the plug works

any idea? , do i just bite need a new genuine one or has somebody had this issue and it was something else ?

 

Now sorted , got myself a new sensor from a Skoda Fabia of all cars , worked instantly