Reverse sensor problem
 

I have a 2005 f350 with the park assist sensors I have 4 the two middle ones work the end two don't work unless you rub them if I swap the middle two for the end two then they work on the middle and i was told if it was wireing then it would not work at all the system works because it stays on in reverse. The module is new aswell as the back end wireing what could be the problem anyone know. Kinda lost as to what's wrong with the end two even bought new sensors and they did the same thing

How much wire do you have back there? Can you undo the wiring holders and move the sensors around while they are still plugged in? Or leave the sensors mounted, but move the outside wires to the inside sensors and the inside wire to the outside sensors? You may not have enough wire, but would be curious what it would do then.

Any other help really trying to figure this out