Rear air bags not inflating, but the front is working properly. There is compressed air at the two rear solenoids, but the solenoids are not being energized to allow the air into the rear airbags so they can inflate. I realize the air suspension control module provides the signal to energize the rear solenoids(don't want to replace the module unless all the inputs are verified as good),but there have to be some ENABLE siganls that have to be satisfied before the control module will energize the 2 rear solenoids. Is there a rear height sensor that could falsely tell the module that the rear air bags are fully inflated when they are not? This is the kind of thing I'm looking for? What conditions have to be satisfied before the 2 rear solenoids receive their enable signal. My compressor, drier, solid state relay and all the air lines are OK. The front airbags work properly so the front solenoids and the required enable signals are all good. It's the missing enable signals in the rear that has me stumped. There isn't much left, but I don't want to buy a control module unless I have to.