I have a 1998 Lincoln Navigator 4x4. My Check suspention light has came on and off over the last few months. Now I have noticed that my rear is extremely low and my air compressor is not kicking on. I tried reseting the system by switch the air suspention switch under the dash didnt work. When I unplug the compressor I see 4 wires Red,Black,LT Blue,White. Hook the red wire to power and the black to ground I can get the pump to kick on fine but my rear stays to the ground i even jacked up the rear while the pump was going and it dosnt seem any air is getting to the bags. I have a few questions. When I jump it to get the pump to work is there a reason why my rear of my navi wont air up. What is the blue and white wire for? I figure the relay probably went bad but why when I bypass the pump it wont air up there rear. Is there a electronic air release valve or something. Thank you for all your help.