Load level suspension

[s.cummings]

Hi does any one have a electrical diagram for the air suspension on a 1998 Olds Silhouette my air compressor has quit working and it won't start with the manuel switch either so I would like to know what wire to run the 12 volts to to get it to run. thanks Steve

[merc81]

My scanner is not available at the moment, but you can't access the air pump motor directly. It gets power from an internal relay that can open to shut off the pump.
Motor power is supplied on orange wire to pin E with ground on black at pin G. The internal relay can fail open however so that's not a great way to test.


If its a 98, best to pull the whole assembly down from the van and put it up on the shop bench for a complete overhaul. The pump is a single piston type and it can seize up from moisture coming in with the inlet air. Nothing tricky on the pump assembly, you can pretty much just look it over and see where to start unscrewing. Open the crank shaft area and lube the under side of the piston and crank. Also, open the head area up and clean out the crap that builds up in there around the relay.
The head screws can be stuck, so use penetrating oil and maybe come back every day until they come free.
John

[s.cummings]

Great thanks I went looking in the old threads and found a pic of the wiring diagram but you are right it likley needs a rebuild anyway. Hey you won't know what the relay is for that is right on the back of the bracket that holds the pump do you ??
PS it is a 1998

[merc81]

its one of the power relays that control the pump motor.
John

[rockwood84]

the compressor head on these weren't sealed correctly at the factory and being right behind the rear tire the tire throws water on the compressor head. once the water enters the head it causes it to short out. the compressor head is what keeps the air in as the pump pumps it.and lets it out when it is no longer needed.g.m. only wants $140.00 for a compressor head. but the main problem i see is the seal at the top of the compressor head not keeping the water out.the fuse on a '98 is in the fuse box passengerside dash. it is elc 25amp bet the fuse is blown if so then check for rust and corrosion in the compressor head.