Big Car Club - MPV and SUV Forums

My rear parking sensors are not working just get the continuous beep when selecting reverse,vcds shows all 4 sensors are faulty. Anyone any experience of this is it likely to be all sensors at fault or a wiring problem? I don't mind changing sensors just don't want to replace them if they are not the fault. Apart from vcds is there any way to test them individually?

Has it done this since you owned the vehicle? I find it quite unlikely all four sensors would pack up, more probable that a common live feed or earth to the sensors has failed. The wiring diagram (https://www.fordmpv.com/smf2/ford-galaxy-reference-library/galaxy-parking-sensor-faults-pdc-systen-(mk2)/msg13813/#msg13813) shows a common branched red and brown wire to each of the rear sensors, which I'm assuming is live and earth, with a third (I'm assuming) signal wire, it's only the signal wire that is unique to each sensor and a different colour so if you've lost a live feed or the earth at the multiplug end (or there's corrosion) where the loom connects back to the body wiring it could have shut all the rear sensors down.

Thanks for reply.

Yes has done it ever since I got car but sorting other issues this one been on back burner.
Cheers for wiring diagram will have a poke around with the fluke and see what's going on.

Hi johnnyroper

For the sake of less than a tenner get yourself a VCDS lead and scan the park assist module.
The wiring can be a bit delicate and unnecessary fiddling with the wiring may give you more problems than you had to start with.
It's also a very useful tool to have when diagnosing other faults on the car.

I have got vcds and already scanned it to find 4 fault codes 1 for each sensor.

 [OOPS] my bad should have read first post.

Finally found time to check this out.

12v to all sensors and good earth when all switched on,checked wiring from control unit to sensors all ok at 0.1ohms so either I have a duff control unit or all 4 sensors are indeed u/s.
The control unit is not water damaged so I am leaning towards sensors got a 50/50 chance of sorting it no matter what part I change.