Dead air suspension

[lxman1]

Hello,
newbee to the forum, but not to Lincolns. I am currently trying to repair my father in-laws 1996 Lincoln Conti.
The air suspension is dead. The compressor runs fine if I run 12V to it from the battery, so it's not that. It shows air susp. OK in the diagnostics, but does not work. I even found and swapped out the suspension module in the trunk (that looks like an ECM). This seemed to get rid of the ABS and Traction control lights that were on.
It's like the system is getting no power. I have checked every fuse and relay that I know of both under the dash and under the hood. All are good.
Any ideas on where the lost power has gone?
I appreciate any help that you can give. I am buying a 96 Ford shop manual for this car, but it will be next week before it gets here.

Thanks,
Jimmy

 

[aaronearles]

I'm in a very similar situation.

I purchased a 98 last week and it was sitting on the ground with little to no air in the bags, so I get it home and jacked up, test the compressor with direct 12v, it's good. Test the solenoids with direct 12v, both good. Manually fill the bags by opening the solenoids with 12v and running the compressor with 12v, bags fill and hold air for days.

I start the car, and get "Check Ride Control" immediately. The guy I bought it from tells me the car was up and had no error message when he parked it, but it's been sitting for a year, and eventually leaked all the air out of the system. So the compressor is not seized, the lines, solenoids, and bags are all good. I have no way to test ride height sensors, and I have no power coming out of the compressor relay at any time, but I think that's because the system detects an error, and never tries to turn the relay on.

So I'm down to the following possibilities:

Bad Compressor Relay
Bad Ride Height Sensor/s
Bad Vehicle Dynamics Control Module

Right? It doesn't seem like any of these would go bad from sitting, but I don't know...
I did take the covers off the height sensors, and the circuit board underneath looks good on both, no burns or anything obvious. I also opened the Control Module, and there is no visible damage to it either, although when I start the car with it unplugged, I get no error message, it's like the car doesnt even have the air ride system. Plug it back in, and I get the message, so I'm thinking that the VDCM is what checks the systems components and displays the error message, so it must/should be good?

I've read that the relay only goes bad from excessive running of the compressor, like with a leak, so it doesnt make a lot of sense for that to be bad.

What do you guys think? If I can't figure it out, I'm going to disconnect the control module so no error msg is displayed, and run a switch in the trunk to manually feed the solenoids and compressor 12v so that I can manually fill the bags once in a while as they slowly leak. Any idea how long the system holds air with no major leaks, I'm thinking I could fill it everytime I fill the gas tank if I'm lucky, or of course less often would be nice.


Sorry to hijack thread, I just thought some of my troubleshooting/findings might help you too.