valve wont dump

so today i go to park the truck and the driver side wont empty out. all the other valves dump but the right one doesnt.the guy who bagged the truck has hella wires under the bed so its hard to work with them right now. wat can be the probelm?i hit every switch on the switch box and wen i go for right rear it dont dump,it lifts but doesnt drop.

mabey a ground on that dump came loose.

dump problems are usually electical or maybe cold weather. fill problems are usually trash on the diaphragm.

ya it was electrical after i took aprt the shit the guy had i checked the switch box n there was the problem,but now i get to clean up the mess the guy made,thanx for the help