Ok so I had the cab off to fix headgaskets and what not... so today i switched the switch to 4x4 high... nothing... no light no nothing... switching to low... nothing.... pushed the back up sensor mute button... nothing.... backed up to a wall no sensors..... so I is there something I can look at or check to see whats going on? the green lights to illuminate the button are on... but neither switch does anything... just trying to figure out if its something they didnt plug back up? the shop is 45 mins away so if its something I can fix I would like to do that before driving out there... also when i turn the 4x4 switch I hear no vacuum turn on and I unplugged the 2 hoses on the bottom of the solenoid to see if I could get the pump to turn on and the remainder air that was in the system drained out... but the pump didnt turn on... thanks again guys oh and its a 08 f250