ffl3883

Hello,

I have a 99 LX470. I just got it for $7000. It has 140K miles. I noticed the AHC Off light blinks as soon as I start driving. There is solid green light at N all the time. I also noticed that the AHC H, N, L control button does not work. When I press High, the light would blink a few second at H, then the solid light remains at N. Same goes when I press Low button. I was wondering if this is a safety issue on the suspension that I must bring to Lexus dealer to fix ? How much would it likely to cost for diagnosis and fix? If anyone had similar issue , it would be great if you could share your experience.

Regards

Felix

hankinid

Did you check the fluid level? If so, did it look clear and relatively clean, or more like coffee that's sat all day at a truck stop? First thing would do is change the fluid and see what happens. Your control button sounds like it's working fine. I doubt it's a safety issue, as AHC will force the truck to raise at a relatively low forward speed. A Lexus dealer is not necessary, some 100 series Land Cruisers had ahc so you could see a Toyota dealer. Personally, I find more expertise and talent at a good indy shop, if you have one near you.

silverbul

I have a 03 LX470 & had the same problem. I flushed my system out myself and it still flashed. Stay luminated & level off. Once I pull off it starts flashing. I found my problem & fixed it. The truck has 3 height sensors, 2 in the front and 1 in the rear. Well long story short, I had a wire on the driverside break completely off at the connector. Just went to the salvage yard and took a wire off another wreck Toyota. Splice & reconnect. Problem solved

ffl3883

I checked the fluid. Its below min level and color looks dark. I will definitely change that. Thanks for the Toyota dealer tip.

ffl3883

Thats amazing. How much do the 3 sensors cost by the way ? I am going to check the wiring as well.

silverbul

Last time I was quoted like $380 a piece. & it's not really a sensor

hankinid

Closer to ~ $200 each...check eBay. Stupid-simple to install and adjust.

hth

ffl3883

I had the truck scanned. It was indeed faulty Left Front Sensor. Is there any DIY or resource showing how to replace ?

Thanks

Felix

silverbul

If you have a new one. Just simply unplug & remove the 2 10mm bolts. No need to remove the wheel.

hankinid

You are welcome. Get to the 100 series forum on ih8mud.com and search for something like 'front height sensor replacement'.

Steve

ffl3883

Thank you for your reply. Could you verify if this is the right part for Left Front Position ? Ebay Link

ffl3883

Cool. Sounds doable by myself. I found one on ebay. Not sure if this is the right one for 99 Lx470. Looks little different from the one on my truck.

hankinid

Go to an online Lexus parts website and double check...you've got the same internet as I have and that's all I'd need to do.

ffl3883

Thank you for your reply. Tonight, I went over a small bump on the through-way. The off light stopped blinking and I got solid green light on N. I felt ride become much more stiffer. After I parked the truck, I tried using the height control. When I pressed H, the light at H blinked constantly while light at N remained solid. There was no movement on height. When I pressed L, the light on L blinked constantly , while light at N remains solid. I got movement this time, however only the front moved. My truck was low in the front and high at the back. The height went back to normal position after I restarted the truck. Any thoughts or guidance are appreciated.

Regard

Fliu

hankinid

My next step would be to disconnect the 3 sensors and check resistance, look for loose wires, and anything electrically related. It sounds to me like an intermittent connection. If the pump is starting to die that could cause decreased pressures with resulting slower lift time. Pressures can be checked with a diy pressure gauge, or easier for ~ $100 or so at a shop knowledgeable in Toyota AHC. You could also consider reaching out to user name PADDO here. To say he's knowledgeable in AHC would be the understatement of the year.

Steve