Hi, I have a question about the elc system on my 01 bonneville. I know it should cycle every time the ignition is turned on but on mine very seldom do you ever hear it. I pulled both air lines off the shocks but didnt hear any air come out. the car sits nice and level unless there is a load in the trunk, then it will sag but there is still no sound of the compressor cycling. My question is, would the car still sit level if the system is not working? Should air come out if I disconnect the air lines or is there a one way valve in the shock or something. Any info would be appreciated, I cant stand it if i think something is wrong with my car if ya know what I mean. thanks.

The point of a load leveling system is to level the car when weight is added...if your car is on and you sit in the trunk say and it does not raise and there'* no sound of the compressor coming on...chances are something is wrong. Wait for gearheads to give you ways to diagnose...

with no air assist, your car will sit level by itself. if the air system is working, if you pull a air line from the strut, you will hear air escape, the system pressurizes on keyon. you said you don't hear the system on keyon, could be no power or the level switch is bad. the level switch is the brains of the elc system.

thanks for the replies, I bought the car about 3 months ago and noticed it would cycle(the compressor) about 3 or 4 key ons in a row and then I wouldnt hear it for probably 15 to 20 key ons, and continue on that pattern up until recently now where I havnt heard it in several weeks. Is that leveling switch difficult to replace if that is the problem?

Not sure how it is on these, but my ELC didn't work on my 94, and it turned out to be the fuse...

If you plan on keeping this car for a while, which we'd all hope I am sure, getting the shop manuals for it would not hurt (in my opinion) and in there would be the diagnostics on how to troubleshoot your issue...

You can usually eBay for the manuals or find them somewhere else on the net... I got a set for my 95 and they've been the best money spent yet for me...

In the meantime, this link should be able to help you out.
Suspension Control ( Automatic - Electronic Level )