LX570 AHC “Basics” - Added as sticky thread for AHC Issues (3 Viewers)

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It's not a 100, so there are different metrics.
1) The raise and lower time should be reasonable (like 15 seconds)
2) the reservoir is behind the right side rear tire. You'll need a flashlight in by the spare tire shining toward the right rear tire to illuminate. Verify fluid level. To pull a sample you'll have to open a bleed valve at an accumulator. Make sure you know this will collapse the suspension due to pressure release, so don't hurt yourself.
3) Shocks could weep at the seals, otherwise they don't have a failure mode. springs get old with time, so they might be due. If you decide to refresh the entire AHC you are looking at $2k or so for accumulators, shocks, and springs, excluding labor. only a couple of people have needed to do this so far.
4) yep
Can I not just use something to pull out a few drops of fluid from the engine bay? The 14 tics thing. Should I worry about that? I will be inspecting lines for rust etc., Moreover this vehicle is a true mall cruiser so the AHC has not been stressed really. Its just the age (150,000 miles)
 
Can I not just use something to pull out a few drops of fluid from the engine bay? The 14 tics thing. Should I worry about that? I will be inspecting lines for rust etc., Moreover this vehicle is a true mall cruiser so the AHC has not been stressed really. Its just the age (150,000 miles)
The reservoir Nd pump are not under the hood, they’re behind the right rear tire. If you’re lookin at a 100 then yea it’s under the hood, and what I said above doesn’t apply.
True mall crawler or not if the necessary minimum maintenance wasn’t done you should r and r. And the nitrogen creep from the accumulators is a function of time.
 
When I bled my AHC I ended up with a few cm's of oil higher in the reservoir. No dramas.
 
I am wondering apart from pulling the carfax/Autocheck (I just need VIN I guess), what else should I check.

Not trying to hijack the AHC conversation and you may have already seen this in another post. If the radiator is original, it will almost certainly go bad relatively soon. Not a reason to not buy the truck, just an FYI. Check out this LOOOONNNGGG thread on it.
 
I recently started noticing some odd AHC activities/movements. The at speed lowering is getting awkward, lowering corners at noticeably different times and rates. Hard resets at stop conditions and such...so I started researching and ended up going through this entire string. Seems like it is the location for my question. 2017 LX with 70k miles. Bought certified at 58k. I do not believe the dealer did ANY of the 60k service they said they did. Anyway, it is a teacher parking lot car 95% of the time. The other 5% is spent on campling trips up into Georgia/NC and even a 7k loop out to SD, MT, CO etc.... We tow a 3k-ish offroad trailer (BRX) and generally try to camp where others don't. The LX gets a little work on our trips. 285/65/18 AT's, a winch and a prinsu is all I have done to it. Below is a pic of the AHC reservoir in N and on a flat surface. Is that anything to be concerned about or should I just flush and wear? Note that the closest Lexus service center is Mobile, AL, about 2.5hrs from me.

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Don’t stress - flush it and just check around for leaks - southern car? Also I’m in Pensacola if you need help!
 
Alabama...bought it at Birmingham Lexus. Gonna do the flush this week. You happen to be going on the Panhandle Toyo Blackwater River Trip next weekend?
I really gotta join that group lol - yeah I’ll be there!
 
You might want to add fluid so you are at least to min level in normal mode. The fluid looks pink in the reservoir, which is good but a flush to make sure is a low hurdle to clear.
 
You might want to add fluid so you are at least to min level in normal mode. The fluid looks pink in the reservoir, which is good but a flush to make sure is a low hurdle to clear.
Do you think that level could be making it wonky or is there another component that may be doing both? In hind site I do believe it has been having trouble keeping the trailer tongue where it should be.
 
Just finished bleeding the 5th accumulator. It's right next to the muffler under a metal plate. #12 wrench loosens the 3 bolts on the plate. A ratchet won't fit. I loosened the plate keeping the bolts in place, stuck a #10 wrench on the bleeder with a hose on it and moved the bleeder about 1/8th of a turn. That is about all there is room for. Took out about 1/2 qt. Pulled the pos. cable, added about 1/2 qt, Dropped the jack. Reattached battery. Hit the starter button to wake the car up. Hit it again waited for the pump to stop making a noise. Then Started it up. The system did it's thing. Looks like I gained 1/2" on the back and the front has moved up 1" more after finally bleeding the last accumulator. I'm hoping this will help the ride and handling a little bit better at high speed.
So...why disconnect the battery here?
 
I was being cautious. I disconnected the battery so the pump wouldn't pump until I wanted it too. Pumping air into that system would be no bueno. I've only owned this truck for a short time and I'm not exactly sure when the pump powers up.
 
Is there a similar thread here for tuning the AHC system on a 200 series. I found the one that @PADDO was guiding for the 100 series (admittedly, i found that on my phone and haven't spent the time to read all the way through it, so there may be 200 series specific info in there). Not asking for a thread on flushing the system, i know there are plenty of those, including this one.

That thread covered things like how much fluid the system used to go from L to H setting (number of ticks on the reservoir) to determine the state of the globes. As well as, reading the pressures on each accumulator through techstream and using that info to keep your suspension within specs. Fixes being to lower height via sensors or replacing/spacing springs to lessen the load on the front/rear accumulators.

Does most of the info from the 100 series apply to the 200? IE 7+ ticks on the reservoir being what you want to see to get from L to H. And pressures on the accumulators being between 6-7 (forgot units).

EDIT: (found in another thread) link

CanadianRockyCruiser said:
After 11 years of 100 series ownership, I bought a 2013 LX570 and sold my 2001 LX470. I'm glad we can use the same AHC tricks with the 200 series! Thanks to all who have explored the sensor lift. This will probably be my first modification, after I put on some proper winter tires tomorrow (bought some Tundra 18" rims, and will put Hakkapeliitta R3 275/65/18's on tomorrow). I look forward to a sensor lift and some larger all-season tires in the spring.

One question I've got: With my 100 series I would always check the "neutral pressures" to make sure that I wasn't overloading the system (I put on bumpers, winch, roof rack, sliders...). On the 100 series stock pressures are 6.9 MPa +/- 0.5MPa on the front and 5.6 to 6.7 MPa on the rear. Do we know what the neutral pressures are for the stock 200 series (LX 570)? That would probably give us a good target for adding rear spring spacers and front coil spring spacers (trial and error). Is it in the LX570 shop manual?

Normal pressure is 8 MPa (1160 psi) and will reach 13MPa (1885 psi) from Normal to High.
High Pressure Errors will trigger if you reach 18.5MPa for more than .3 seconds....That's 2683psi!
Low Pressure will trigger at .6MPa (87psi) if longer than .6 seconds
 
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Has anyone ever noticed the AHC pump randomly running during extremely cold temperatures?

Currently at 9,000’ and 20 degrees Fahrenheit. I ran out to pick up the gear we had left out, and I noticed an electronic humming sound. Didn’t think much of it until I noticed it was coming from the rig. Rear passenger side.
I was too cold to investigate, so I started her up, no errors or dash lights, and then shut her down. No more humming. 🤷🏻‍♂️
 
If you were stopped for a few hours it’s your Evap doing a test?
 

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