528it SLS issues

[wolfbone1971]

I had noticed that when my wagon sat for a week or so that the rear was lower. I turned on the car and it raised itself up. Drove it a few days later and all seemed fine. Until I drove it longer. The level light came out. I have had this happen in the past from other e39 wagons I owned so I decided to just to buy the spring/air bag upgrade kit from England.

Got the upgrade kit and could not get the spring in there with any spring compressor I found. So I bought new air bags and new sensors and arms and put it all back together. Turn the key to on, and the compressor ran for a second and then off. I still had the car on the lift so I thought I needed it to be literally on the ground to self adjust. Nope. Never would run. I tried resetting the code by undoing the battery for 15minutes and to no avail still nothing. I then drove it around the block to see if moving it would make it work. Notta.

1. I made a jumper to run the compressor and open the solenoid to at least get it off the ground.
2. I removed the tire on one side and moved the sensor arm up and down to see if I had maybe put it on wrong. Nothing

I have found a pretty good layout of how it operates and wonder what makes the compressor come on when I reattach the battery cable. Also do I have a bad ECH module? Where do the sensors get there power?

[CPHES]

I had a compressor that would run, but not generate pressure.