The sensors fitted to the bumper are actually in two parts, a holder, the outer part & the sensor itself, the inner part
.
If you look on the rear of the sensors you should be able too see that the outer part has two clips (part of the holder) on it that holds the centre part (sensor), release the clips & push the sensor through (easier said than done
) from the painted side of the bumper (out of the back of the bumper), once this is out, the outer part (the sensor holder) pushes out the other way from the rear (back of the bumper) out through the painted side, I'm pretty sure that's how they are removed
.
There's always the possibility that I could be wrong
(I have removed quite a few, but I can't be 100% certain that that's how they come out, I'm 98% sure
).