I have a '03 GX470 (137k miles), and it appears (and feels) like I've lost the suspension system. Two days after a day-trip with six passengers, I couldn't drive it to work; the bounce was so bad, I turned around at the corner and went back home. My mechanic is still looking into it, but he did determine the pump for the air suspension is not turning on. I can also tell how it sits a little lower in the rear. Any thoughts or experience with this issue? Could be a bad pump, or is there a relay or fuse that could be the problem?

thanks...

 

If its all original then you probably have a bad compressor and or leaking air bags and or height sensors. There is a lot that can go wrong but 137.000 miles I would suspect all. Read your manual and locate any fuses or relays that are mentioned in the manual check those first. Then move on.

 

Three potential issues; okay thanks for the response.

 

Sometimes it's a daisy-chain of failures - the bag develops a leak, so the compressor runs longer -- and burns out.

Agree - check fuses first. Then relays. Then check voltages at the pump connector (you'll need a helper to move the console switch from Lo to Hi and back again)

Chip H.