I converted the air suspension to standard struts on my LS430 ultra about 3 years ago. A few weeks ago the "Height High" warning message started coming on randomly. I took the rear height sensors off and tried to check them with an ohm meter. All combinations with the 3 pins just acted like an open circuit. Since most of the blogs talked about a height sensor failure causing the warning message, and the rear sensors were available on EBAY, I decided to just replace both rear sensors with new OEM sensors. After I put them in I started the car and the message immediately came on. I shut it off and disconnected the battery for 10 minutes. Started it up again the the warning message was gone. Drove it twice for 5 to 15 miles with no message. Third time i was driving it the message started coming back on and off. Now it is staying on.

Does this mean my front sensors are the cause of the problem? Why did it act ok for 2 rides and then start the warning again on the 3rd message? The front sensors seem to cost about twice as much as the rear sensors. Is there anyway to test them to see which one is bad?

 

Thanks. I’ll have to find a shop or someone that can read C codes.

 

Also check to make sure you did not accidentally turn the height selector switch to "HIGH".

 

I know it’s not the switch. I tried flipping it back and forth to see if it would affect the warning. Thanks

 

Another long shot... Did you remove the 20A fuse called "AIRSUS" in the drive-side fuse box when you made the conversion 3 years ago?

 

I just went through the same thing; also a UL with Air Suspension removed many years ago.
I threw a code indicating RR sensor only.
I took sensor apart; easy with just 4 phillips screws.
Moisture had got in; the 3 brass plated screws that connect the incoming wires to the resistance circuits that reside on the ceramic flat cover plate all had rust on their ends.
I sanded all the screws and reinstalled; lasted almost a year IIRC.
Sanded all again; only lasted 3 months.
Then went to eBay and found the sensors, from Dorman and also no-name; ranging in price from $12 to $200.
I gambled on the Dorman that claimed it was re-engineered to keep moisture out.

Working like a charm after a couple of months.

I'd start start with a code reader and go from there.
But certainly no need to pay Toyota/Lexus prices for complete sensors + levers + connecting links; just swap out the sensor itself onto the frame assembly.

best,
Coker

 

I tried taking that fuse out last week. It gets rid of the height message but generates a message about the auto leveling headlights. Thanks

 

Corker. Good to know you can take those sensors apart and clean them. I will give that a try. Thanks