98 cad deville, 118,000 miles. rear suspension inoperable. 4 components-2 air bags, ride sensor, air pump, and fuse and/or relay. Need to know: where do i start the process of elimination? Possible to hook up auxillary air compressor, unplug the air connection to the air shock and try to insert compressed air or if the air bags are ok, do i take a chance on bursting it? if air bags ok, then, how do i figure out what the problem is without replacing operable parts? Thank whoever for input.

Start by loading the trunk with a body.....uh, buddy or two. Does the compressor run? If not, start with that. Check the fuses, see if it is getting power when it should. Also make sure the actuator arm is connected and not hanging loose. If the pump runs like it is supposed to, then check for a disconnected or broken line. Also check for DTC's. I think there are some for that system.

Mine's been tested with a body or two... but it IS a hearse. :) I had some leaves and grass and mud on the actuator arms when I got it, but a few minutes with hose underneath had things working nicely again. Easy, cheap fix. How often do you get that? Go figure, somebody had been driving it on muddy, wet grass. I'm not sure how much cargo I'm good for, but with over 1200 lbs on a recent (package, not stiff) delivery, it still rode level. Slow as hell, but it's an '85 with 4.1, so....