97 Park Ave self leveling system

[lanceharrington]

The rear self leveling system in my 97 Park Ave Ultra has stopped working. Any suggestions on trouble shooting? I believe it is called ELC sys, please correct me if I am wrong. Have checked all fuses and found non blown. To many wires going to the sensor to figure out which ones to jumper, any suggestions? Can the compressor be direct tested and which wires would it be? I believe the system should come on after 45 seconds with the key in the on position and car not moving. Thanks, Lance

[TopherS]

So far, knock on wood, I've not had problems with my auto-levelers on this car, but on the Roadmaster sedan I had before, I was having problems.

When you say it stopped working, do you mean that the compressor no longer runs or do you mean that the system runs, but no longer levels out the back end of the car? It will make a big difference in where to go next.

The trouble with my Roadmaster was due to a leak in the system somewhere, so the back end wouldn't stay level. The compressor would come on about every 5-7 minutes or so...24/7 (the system in the Roadmaster is always active, even without the key in the ignition). If you turn your key on and there is a significant weight in the back end of the car and the compressor is running, but the back end is not leveling, then there's a leak somewhere...could be in the air-shocks or in the lines or even a problem with the compressor. If the car is simply not trying to level itself out, where the compressor is not even running at all, then my bet is on the compressor. I know that you've checked the fuses, but you might double check to be sure that ALL fuses are checked...including the fuse block under the hood. It seems there are fuses that protect other fuses in there. I remember seeing in the diagnostic for the Roadmaster that there is a way to troubleshoot the compressor electronically, but I can't remember how.

You also might check at your local library. A couple of the libraries around here have some of the diagnostic books (used at the dealerships) located in their reference sections. They also contain the wiring diagrams and troubleshooting steps in them.

Sorry, I wish I could be more helpful.

[lanceharrington]

Topher, thanks for the reply. The compressor does not come on at all. I have taken the compressor out and did a direct wiring and it did not come on. I do not understand the Exhaust Solenoid circuit. Is it a contact closure or is it 12dc input? I have 2 white wires going into the top of the compressor. I found my 95 PA service manuals and it looks like the same compressor design. The manuel says there is a orange and white wire on the 95, but mine has 2 white wires. If I remember correctly orange is a control voltage. Thanks, Lance