skrk

2009 Lexus LX 570

Can we turn off or disable AHC permanently, it stopped working and the dealer is charging 9k, and other shops have no idea how to fix it.

it stopped working - very bouncy and wabbles, sometimes stuck in low or high, sometimes tilted to the left

I need a shop that can fix it
OR
Can we turn off or disable AHC permanently, is it safe to disable?

any help is really appreciated

Misteracng

I think you cannot simple disable it because it is integral to the suspension as it takes the place of the shock absorbers. I think you would have to completely remove the system and replace with appropriate shock absorbers. Repair is probably the better option. 9k seems high but I guess it depends on what needs to be fixed. Unless the shock assemblies are blown and leaking they should not need replacement. Your symptoms of bouncy ride seem to point to worn accumulators, that is the most common repair. Parts are not that expensive. Many youtube videos on your exact symptoms. Those can be swapped pretty easily, just need to bleed the system correctly. If that is the case, I cant see that costing 9k. Its more likely the dealer doesn't really know whats wrong and is just quoting a bunch of parts. Now if you have significant rust issues with lines and leaking or hydraulic pump failures then that's a bigger issue.

skrk

It is rusted but we don't see any leaks, we changed the sensors, and the bleed is not working it is not flowing through correctly.

Misteracng

Can you describe what is exactly happening when you bleed? You need to fill extra fluid in the reservoir, then set to normal height, wait 30 seconds to make sure normal level is reached then engine off. Then you attach a hose and bleed drivers front first till all fluid comes out if flushing, otherwise wait for all air bubbles to stop coming out if bleeding air. you may have to add more fluid and raise it up and do it again until complete. Based on what you said, if you have original accumulators and high miles they are probably worn out. I think that will probably explain your symptoms. So even a proper bleed will not solve your issue until other issues are solved. It could be possible that you just have air in the system, but that should not happen unless you run low on fluid and it draws air in.

skrk

A long story will try to make it short and this is what happens....

I want to do a 120k-130k mileage maintenance service, so took the truck to the shop where the previous owner did the service
1. Steering fluid change
2. Diff. lock fluid change
3. Break fluid change
4. AHC fluid change

After AHC fluid changes the system did not work and it was working before (The only issue I had was AHC did not work in cold temperatures) so I thought the
fluid change would fix it, the mechanic said the shock are fully rusted that is why it not bleeding!!! so we installed new shocks but it got worse a small speed bump or a pothole shook the entire vehicle and it wabbled.

So took it to the dealer to run a diagnosis and they said I have to replace the sensors the motor and the pump for 9k. Changed the sensor same issue.

Any idea!!!!

Misteracng

This seems strange. If the AHC was working prior to a fluid change, then it doesnt work after, then most likely the fluid change was done incorrectly. As soon as you open the bleeder to drain that shock will compress and the car will drop down on that corner as the fluid comes out. This is what happens per toyota manual. If you cannot "bleed" due to a rusted shock then the shock would have to be stuck and unable to compress. This would be quite obvious in driving regardless of AHC. If the shock is blown and not holding pressure I would imagine it would be leaking large amounts of fluid and the shock would not level up at all and you say there are no leaks so doesnt seem likely. I would just say that AHC service is not actually difficult, but its can be easy to mess up. Seems getting air into the system, and then not getting it out its the most common mistake. It can be corrected, just takes time. Its similar to brake bleeding really. Again if the system really has wobbles and poor control, most videos I have seen point to the accumulators needing replacement. Your 2009 its definately at the age that the accumulators might fail. If the dealer really thinks the whole system is done, you really should get a report of what codes they saw. At 9k you really should get a second opinion from someone who really understands AHC to confirm. Im not against dealers, but they are really big on replacing parts rather then properly diagnosing and fixing. Also these are really low production cars, I doubt most technicians deal with the system often.

skrk

Thanks for the quick reply
I asked the dealer to give an estimate to bleed the AHC fluid they quoted $650, I asked the local mechanic if he could do that he said yes, I am hoping he knows how to do it. Let's see if the fluid flows if not I am going to ask them to change the accumulator and see where it goes

Misteracng

This sounds like a plan. just get a proper bleed done and see what problems. Please make sure whoever is doing it knows how to do it per toyota procedure and really has done it before. Dont let someone testout on your car or you will not know for sure what the problem.

skrk

What is the worst-case scenario if I want to replace the entire AHC, what does it need?
1. Motor and pump
2. Accumulator (globe)
3. Sensors
4. Connecting hose
5. what else .............

Misteracng

All this, plus the hard lines throughout. Each corner has a shock body at each wheel, accumulator, shock absorber control valve, suspension control valve (globe). I seriously doubt you would have to change everything. Like the parts other then globes don't seem to fail, unless they are severely rusted or leaking. It seems always to be the globes. If any of the lines were compromised there would be an obviously leak. So if the AHC is actually moving, then it should working. Bouncy and rough ride seems to always be the globes. If you are looking at replacing the entire system, for a car that age, I think it would be not worth the cost. You might as well sell and get another car. Or else, go for a system disable and try to replace with regular shocks.

skrk

system disable and try to replace with regular shocks

I like this! Any idea who can do it? The local place I am trying now has no clue about AHS

Misteracng

That I have no idea, I just seen some forum posts about doing this. You would need some shocks that will fit and some way to disable the warning light.

Ratchey

Start here https://forum.ih8mud.com/threads/dis...ights.1164357/

skrk

Thank you!!! That's a good start I will try, the vehicle is already bouncy and messed up, and I can't drive, I will take the risk and try it out.

skrk

I got lx 570 back home, so the guys in the shop can't figure out what is wrong with AHC system

Looking at my two options
1. https://forum.ih8mud.com/threads/dis...ights.1164357/ Follow this link to disable the AHC permanently. I have to take the risk anything may happen???
2. Replace the accumulator, two images below do I need just the globe or the full accumulator

Can you recommend any site or shop to buy an accumulator, Is there a way I can order from Japan?
any advice is very helpful, thanks




accumulator full set

accumulator globe