i have a 2005 ext and notice that my rear shocks didn't lift i check the relay and jump the contacts to make compressor work.i did notice that when i shut truck off and waited compressor came on but now it won't.I have 12 volts on relay but no ground if i but ground the coil pulls in and relay contacts close and truck lifts. Any ideas what it could be.

 

i just now hard reset the truck and know my service ride control pop up on my dash were it didn't before even when truck wasn't leveling