Rear Height Control Failure

[smaislin]

The other day, I lowered the rear end to load some stuff. Nothing was all that heavy, just bulky so having the back end a bit lower was helpful.

Normally, when you start off, it goes back to normal. However, it actually bottomed out and I had one hell of a nasty drive home. One the way home, I pulled over and tried to get it to raise the rear end by putting the switch to high, but no luck. So, I drove home with the headlights pointing high and really learned about every single bump in the road.

When I got home I called the dealer and they said that it might be OK in the morning after warming up in the garage. It was in the twenties so there was chance that temperature was causing the electronics to malfunction.

The next morning I started the GX and it stayed bottomed out. I put the switch on high and the pump pushed the rear all the way up. I put in back to normal and it dropped to the right stop. I even put a level on the running board to see if it was level, and it was.

So, it seems fine now as far as the ride goes. I have not tried LOW again as I don't want to deal with it. The dealer said that driving with it bottomed out won't hurt anything expect the ride and, of course, if using the headlights I will get lots of people who will give me the middle finger salute (I did get quite a few people on my way home the other night who kept slamming on their brakes). The dealer said that when I have the time, park it outside on a cold night and try it in the morning. If it fails, drive it on down and they can determine exactly what is going wrong.

When it did fail, the normal light kept on blinking for a long time. So, the system probably did register some sort of fault.

Anyway, I thought that I would write about this in case anyone else has experienced the same. One of the problems with all of these electronic systems that adds convenience is that they can get fussy when the temperatures go to extremes.

[denslexusgx470]

strange, when i hauled my pergo floors inside my gx, i didn't touch the air suspension, and wheni got home, it was automatically set on high! <_<

[RAM MAN]

When I got home I called the dealer and they said that it might be OK in the morning after warming up in the garage. It was in the twenties so there was chance that temperature was causing the electronics to malfunction.

The height control system uses compressed air. I’d bet you had a little moisture in the system and it froze up. The electronics should not be affected by the cold.

[ADVocate]

The other day, I lowered the rear end to load some stuff. Nothing was all that heavy, just bulky so having the back end a bit lower was helpful.

Normally, when you start off, it goes back to normal. However, it actually bottomed out and I had one hell of a nasty drive home. One the way home, I pulled over and tried to get it to raise the rear end by putting the switch to high, but no luck. So, I drove home with the headlights pointing high and really learned about every single bump in the road.

When I got home I called the dealer and they said that it might be OK in the morning after warming up in the garage. It was in the twenties so there was chance that temperature was causing the electronics to malfunction.

The next morning I started the GX and it stayed bottomed out. I put the switch on high and the pump pushed the rear all the way up. I put in back to normal and it dropped to the right stop. I even put a level on the running board to see if it was level, and it was.

So, it seems fine now as far as the ride goes. I have not tried LOW again as I don't want to deal with it. The dealer said that driving with it bottomed out won't hurt anything expect the ride and, of course, if using the headlights I will get lots of people who will give me the middle finger salute (I did get quite a few people on my way home the other night who kept slamming on their brakes).  The dealer said that when I have the time, park it outside on a cold night and try it in the morning. If it fails, drive it on down and they can determine exactly what is going wrong.

When it did fail, the normal light kept on blinking for a long time. So, the system probably did register some sort of fault.

Anyway, I thought that I would write about this in case anyone else has experienced the same. One of the problems with all of these electronic systems that adds convenience is that they can get fussy when the temperatures go to extremes.

←

I had a Range Rover with air suspension all four corners. This could be a similar case. The Air Springs are nothing more than rubber cylinders that ride on curved pieces of steel. The natural weight of the truck cause the air seal for the air springs (much like a tire fits its bead on a rim). If you lowered the truck prior to loading your heavy item, this added shifting weight may have been enough to break the bead. The air compressor may have gone into fault mode and not started up again. This also happens when the truck raised on a lift using frame points. Driving your truck to your destination may have caused the beads to seat again. Only after allowing the truck to reset overnight may have cured this. Just a suggestion, since I am not a Toyota or Lexus Mechanic. :whistles: What ever happened, it is pretty weak that the system under that type of condition. Good thing it started to work for you again. Very few things suck as much as riding on the suspension stoppers.

[randy20g]

My height control pump failed a few months ago. They replaced it under warranty.

[denslexusgx470]

My height control pump failed a few months ago. They replaced it under warranty.

←

wow, do u have KDSS?

[randy20g]

No KDSS

[smaislin]

I have lowered and raised the backend to test it a couple of times since this happened and I have had no additional problems. Moisture, unseated beads, who knows? The next time it is really cold I am going to park it outside and run another test. For now, the mystery continues.

Yes, it was quite a ride driving on a bottomed out suspension. It makes you appreciate the concept of not bolting the body to the axles. :)

[denslexusgx470]

I have lowered and raised the backend to test it a couple of times since this happened and I have had no additional problems. Moisture, unseated beads, who knows? The next time it is really cold I am going to park it outside and run another test. For now, the mystery continues.

Yes, it was quite a ride driving on a bottomed out suspension. It makes you appreciate the concept of not bolting the body to the axles.  :)

←

that is strange, because as i said, when i hauled the pergo floors inside my GX, the rear raised up by it's own and stayed up. but after that, it went back to normal height. B)

[strindl]

The other day, I lowered the rear end to load some stuff. Nothing was all that heavy, just bulky so having the back end a bit lower was helpful.

Anyway, I thought that I would write about this in case anyone else has experienced the same. One of the problems with all of these electronic systems that adds convenience is that they can get fussy when the temperatures go to extremes.

←

I did the same as you in bitter below zero temps last night. I was loading an HDTV into the back, and lowered the suspension so I could possibly avoid a hernia. When I got back into the drivers seat and started driving, I had forgotten to raise it back to the normal setting, and I felt how rough tha back end rides like that.

I moved the switch back to Normal rhough, and even at 7 below zero, it went into position and all was well.

[denslexusgx470]

The other day, I lowered the rear end to load some stuff. Nothing was all that heavy, just bulky so having the back end a bit lower was helpful.

Anyway, I thought that I would write about this in case anyone else has experienced the same. One of the problems with all of these electronic systems that adds convenience is that they can get fussy when the temperatures go to extremes.

←

I did the same as you in bitter below zero temps last night. I was loading an HDTV into the back, and lowered the suspension so I could possibly avoid a hernia. When I got back into the drivers seat and started driving, I had forgotten to raise it back to the normal setting, and I felt how rough tha back end rides like that.

I moved the switch back to Normal rhough, and even at 7 below zero, it went into position and all was well.

←

even though you left it in low, it should raise back automatically to normal at around 20mph.

[strindl]

even though you left it in low, it should raise back automatically to normal at around 20mph.

←

Yup, but it didn't take me getting to 20 mph before I felt the difference in ride quality, and remembered that I hadn't put the rear suspension back to normal. Just backing out of the driveway made it obvious.

[denslexusgx470]

what i noticed is that when backing up while the suspension is lowering or raising up, the "clunk" becomes "thug, thug, thug thug thug" until you put the Gx in neutral. weird, but i tried it! lol

[chubyball]

I am experiencing the OFF light flashing constantly, does not mater I push what, the car would not raise height or low itself. Right now the status is N green light is on and OFF light flashing. I assumed this problem cause from moist got into the electronic. Anyone know how to fix this is problem? Is it a comon problem for GX470 2003 model?

[amrish123]

I am experiencing the OFF light flashing constantly, does not mater I push what, the car would not raise height or low itself. Right now the status is N green light is on and OFF light flashing. I assumed this problem cause from moist got into the electronic. Anyone know how to fix this is problem? Is it a comon problem for GX470 2003 model?

I am also experiencing a similar problem with my 2004 GX470. The Rear height control OFF lighting flashes continously and the height control doesn't work. The status is N green light and OFF flashing. It has been like that since yesterday. Chubyball, Did your issue ever get resolved. What was the problem and how did you get it rectified. Any help would be appreciated.

Thanks,

Amrish

[Redhaze737]

Does the rear suspension include any type of shock absorber or is the air ride all there is?

I just started experiencing a 'bottoming out' effect when coming down off of speed bumps. The raise lower function still works but the ride is a little iffy right now. Is the problem the air suspension you think? I hope it's covered by Warranty Direct as it just came off the Lexus 4 year warranty.

[abner]

Good morning!!!

I am experiencing a problem with my 2003 GX470. The Rear height control dash board light flashes continuously and the height control is not working.

Any advice? Thanks!!!

[chrisvr6]

I just ordered bilstein 5100's for the rear to fix the bottoming out. $80 each versus $500 for stock. no more adjusting comfort though.