Help isolating air suspension problem on '99

I've read a few threads on the topic, but being not supremely auto saavy, could use some assistance in isolating a problem with the air suspension nightmare on my expy

Symptoms:
Rear suspension will NOT inflate. Front is holding steady at normal ride height, but rear is completely flat.
1. WAS intermittent. Would occasionally work, but now will not work at all
2. When the vehicle is put into drive after starting, you can hear a pair of clicks coming from the back of the vehicle. (perhaps a mechanical relay trying to engage?)
3. The chk susp idiot light doesn't come on initially. Only after driving for about 15 minutes.

I've read in another thread that this may possibly be due to a worn component (o-ring) within a hose in the front compressor area. I don't have a good schematic of this component. Is this the object located near the washer fluid resevoir?

Is there a way to force the rear compressors to inflate the suspension by bypassing the relay and sensors?

Any help in diagnosing this would be greatly appreciated. I'm too cheap to take it to the dealer and pay their extortionist prices. :(

your vehicle only has one compressor its in the engine compartment and supplies air to both the rear and front. What u hear is probably the solenoids opening(one on each rear bag). Does the compressor come on when you turn the car on? If it doesnt then check all your fuses the ones in the pass compartment too. Their is a way to bypass the compressor relay but I d start with the fuses