I apologize if this is categorized wrong, but am new on here and have a question regarding the ELC on a 1999 Cadillac Deville. When I start the car, I hear the leveling compressor come on...but the rear end doesn't raise. It stays on maybe a few minutes and kicks off. When I sit on the rear end, or add any substantial weight, it doesn't activate. I raised the rear end, and check the compressor. Made sure the hoses weren't leaking back there, and didn't see anything or any air leaks. I tightened them just in case. Started car again, compressor kicks on...but doesn't raise or lower. Kicks off after a few minutes and thats it. Does anyone have any ideas what this could be? The car seems to ride low, and I would like to get this working so it sits correctly, and actually works. Any assistance would be greatly appreciated...

David