LS400 Air suspension – compressor issue

Annoying…. Driving home, need to raise the nose of the car so it doesn’t drag the bumper through this intersection they’re working on. Press the switches, and… Nothing. Seems like the tanks are empty and the compressor isn’t kicking on.

When I got home I checked the fuses first, but they were fine. Quickly checked the wiring in the trunk, everything seemed okay, no shorts, burns, smoke, etc. I figured the tank pressure switch wasn’t working anymore, but a quick test with my DMM said otherwise. The only things left were the relay and the compressor itself. I cut the pump wiring and tested the pump straight off my s13 optima battery — luckily it worked fine… Strangely after I put the wiring back, the relay worked fine too. I really hate intermittent problems. I’m guessing that it was either a poor ground issue (and the relay wasn’t kicking on), or some sort of thermal issue with the relay or compressor. Hope this issue doesn’t come up again!

I’m planning to upgrade to a digital controller and electric solenoids soon, as well as a complete trunk rewire.