Hello, new to the Forum here. I have a 2007 GX470 and after I towed my trailer with it the last time the ride height is not functioning properly. In normal driving it lowers the rear end down to the bump stops. No leaks in the air bags. I put the ride height in the high setting and waited until it was at about the normal height, shut the vehicle off and pulled the 50amp air sus fuse. It stays at that height and the 4 position shock adjuster is working fine and it drives like normal. I'm guessing it's the ride height sensors but I don't know. Is there anything else to look at before I throw a bunch of money at new sensors?

 

When were the air bags last changed?
If there is no change in height when parked doesn't mean the bags are good - sometimes they have small cracks in the folds that don't show up until there is weight added (passengers, hitch)

Are you in the rust belt?

Thanks.
Chip H.

 

I don't think they have ever been changed. I bought it with 62,000 on it and it now has exactly 70k. I'm in the rust belt but it's a pretty clean undercarriage for coming from Illinois. I've been driving it since Sunday with no issues And I had about 100 lb of tools and a case of bottled water and the back.

 

Check the sensors, maybe a linkage binding or electrical issue in the sensor. They are easy to test. And I think Rockauto has some cheap ones, like $60?

 

You can test it yourself. I have not personally done this but looking at my guides...

1. Remove the sensor arm
2. Unplug the connector
3. At the sensor side connector apply +5v to pin 1, and ground to pin 3
4. You should see a variable voltage on pin 2. As you move the arm it should *smoothly* change from about 0.5 volts to 4.5 volts.

The emphasis is on "smoothly" - if there is a dead spot inside the sensor you'll see the voltage jump around, and that's your sign to replace it.

But .. there are people who have opened them up and cleaned the resistor trace inside with electrical contact cleaner.

If you don't need the vehicle as a daily driver and can let it sit while it's apart, you can try that.
Cheap if it works - annoying if it doesn't because you can't start the vehicle until a new sensor is put in (the ECU would probably try and overinflate the bags)

Chip H.