RTH: AHC system just let go (out of the blue)

[bloc]

I’m curious how much of this is the pump actually failing vs just getting clogged with debris.

Any chance you kept the old pump and can tear it down?

 

[TeCKis300]

I'd be confident in most Lexus dealers at this point. As has been said, these hydraulic suspension systems are not new and have existed in the prior LX470 since 2001. The 200-series AHC system is slightly different but operates on the same principles. Yes the LX is not sold in huge numbers but there should be seasoned techs familiar with them.

The rash of AHC Lexus dealership issues in recent past was due to fluid contamination which would cause anyone issues.

I’m curious how much of this is the pump actually failing vs just getting clogged with debris.

Any chance you kept the old pump and can tear it down?

It could also be that once the leak developed, the pump was operated dry for too many cycles. Yes, there is a pressure sensor behind the pump, but it'll still run for some duration until the pressure timeout. It's important to diagnose once any symptoms appear.

 

[arbetrader]

I’m curious how much of this is the pump actually failing vs just getting clogged with debris.

Any chance you kept the old pump and can tear it down?

The pump was shot. We tested it under 12v power and it was running, but very very weak (It kind of just made whooshing sounds). As soon as they installed the new one it literally started spitting fluid out of where the pinhole leaks were, it started splattering fluid out. That means corrosion caused the failure, and the old pump was working very hard, thus failed over time. It is is now garbage. Anyway, fwiw it's best to fluidfilm the lines annually I think, that way it would drastically reduce chances of failure. Not sure how the pump would get clogged with debris? I was very careful in my last fluid change, ensuring everything was done very cleanly etc. No debris got in from what I could tell. The corroded line caused this.

 

[Docboy]

The pump was shot. We tested it under 12v power and it was running, but very very weak (It kind of just made whooshing sounds). As soon as they installed the new one it literally started spitting fluid out of where the pinhole leaks were, it started splattering fluid out. That means corrosion caused the failure, and the old pump was working very hard, thus failed over time. It is is now garbage. Anyway, fwiw it's best to fluidfilm the lines annually I think, that way it would drastically reduce chances of failure. Not sure how the pump would get clogged with debris? I was very careful in my last fluid change, ensuring everything was done very cleanly etc. No debris got in from what I could tell. The corroded line caused this.

Glad to hear you got the ahc system resolved. Mind me asking the total cost of repair? How many days, if any, were you without the vehicle?

 

[200 series]

Regency went out of their way to really help me, likely just for my circumstance given there was much corrosion and the job started ballooning far beyond what they had quoted me. They even provided a free loaner car for a few days (2025 NX). Yes, it cost well into the thousands, but that being said most of the lines are all new (at least all the rear lines) - I might look into the front lines and new globes in 4 years time when the next fluid flush will be due.

Their service was excellent. I can't say enough good about it. The young mechanic that worked on it seemed pretty well versed in this. I had some reservations much like you at the beginning, but not anymore.

By the way, one of the service advisors (I believe it's David - I hope it's okay mentioning his name, he's a board member here too) understands these systems well because he has an LX470, built-out super nice as an adventure rig. He said that their dealership does these LX570 pumps quite often, a few every month from what I recall him saying. He said for some reason they seem to go out on them more than even the LX470s, my hunch is the rearward location making them subject to more corrosion as they age. The 470's reservoir/pump is under the hood which is a better location.

I wouldn't hesitate to take it there again in the future. They'll be doing any AHC work for me in the future but hopefully it won't be necessary.

Amazing to hear, TYSM! A short drive from where we are and will be asking for David!

 

[bloc]

Not sure how the pump would get clogged with debris?

To be clear I’m not saying you did anything wrong. Just going on memory of others opening at least one or two pumps that seemed shot to find very very fine debris at the pump inlet. Once the debris was cleared they primed and worked great.

Over the life of these vehicles it is plausible for extremely fine particulates to make it into the tank through the normal course of operation, due to the near-constant cycling of fluid in and out of the reservoir as the system does its job to maintain ride height and other functions.

Either way, just asking. Personally I’d like to inspect even a truly failed pump to see the mode. Just a curiosity thing.

 

[arbetrader]

To be clear I’m not saying you did anything wrong. Just going on memory of others opening at least one or two pumps that seemed shot to find very very fine debris at the pump inlet. Once the debris was cleared they primed and worked great.

Over the life of these vehicles it is plausible for extremely fine particulates to make it into the tank through the normal course of operation, due to the near-constant cycling of fluid in and out of the reservoir as the system does its job to maintain ride height and other functions.

Either way, just asking. Personally I’d like to inspect even a truly failed pump to see the mode. Just a curiosity thing.

Yeah, anything can happen. It's possible that my system failed due to a combination of issues. Perhaps there could have been some grit in the system, paired with corroded lines.

In any case, it's fixed now. I don't have the old pump. I had the option of taking it home, but the mechanic said it was literally completely shot so they just tossed it.

 

[arbetrader]

Amazing to hear, TYSM! A short drive from where we are and will be asking for David!

Yup, he was great to talk to. A fellow 100 series owner, he'll talk your ear off on his mods and everything. His rig is super clean. Which is good because the systems are related. He knows of some great discount part sources as well, which is great.

 

[arbetrader]

Glad to hear you got the ahc system resolved. Mind me asking the total cost of repair? How many days, if any, were you without the vehicle?

Hey, yeah it's no problem. My repair cost $$$$ because of corroded lines etc, and there was much extra diag time, they were trying to locate additional leaks, and ensure some lines wouldn't cause future problems - IE they had to removed the exhaust and repair a few exhaust related items with it as well.


Sooo... Here's what was originally quoted (NOTE ALL In CDN funds - USD likely will be LESS).

The original diagnosis took longer (more like 3hrs) - they charged me $500(ish) CDN after tax for this, due to the motor still making sounds but they couldn't pinpoint the actual issue until further investigation. The FSM has additional steps in sequence to check in case the answer isn't obvious.

Once the diagnosis was done (that the pump failed and needed replacement), they quoted me 2.4hrs labor for the full replacement including refilling with all new AHC fluid and bleeding the system. $432 CDN.

The part itself (pump) was quoted $4779.31 CDN at the dealer. Obviously I didn't get it there. I ended up paying $1200(ish) after exchange fees for brand new factory sealed pump from JDM planet in Japan. Note: I'll never deal with JDM Planet again due to a mistake they made, unwilling to correct it, cost me $$ (it was THEIR mistake and they refused to reimburse me).

Anyway, so that saved me $3500 on the part (CDN). Shipping was pretty quick - got the item in less than 10 days from order date.

Total cost for install with new fluid/testing/bleed (with a clean LX and minimal corrosion issues) would have been $800 (CDN)

So total diag time, $800 install, $500(ish) diag, and $1200 part = $2500.

But I needed a bunch of new lines, exhaust components, AHC pump mount kit, blah blah, and 12hrs total time = double that price.

It was worth it.

The ride is so much better than even when I bought it (as you guys all know). In the end I'm happy, and if it lasts another 5 years like this prior to new globes that's okay with me. It's worth it for the benefits of this advanced suspension system

 

[200 series]

So total diag time, $800 install, $500(ish) diag, and $1200 part = $2500.

Hey, that's not bad at all! Equivalent to an annual service of some other euro brand at their dealership
I honestly thought it was gonna be in the 5-digits from some other forums that I read lol! Great to see, thanks for sharing!

 

[arbetrader]

Hey, that's not bad at all! Equivalent to an annual service of some other euro brand at their dealership
I honestly thought it was gonna be in the 5-digits from some other forums that I read lol! Great to see, thanks for sharing!

Yeah, it would have been that way if I purchased the actual pump from the dealership, as well as if they didn't discount any labor charges for me. The reality is these are expensive, however I got lucky, the dealer went out of their way to help with reducing what they could, and they were open to allowing me to buy my part from Japan directly (shipping was only a little over a week, so totally reasonable) - to save an extra $3500 CDN there as well.

Provided I don't run into any other AHC line issues (IE front lines etc) before my next fluid change, I'll likely upgrade the globes at that point (can buy all 4 out of Japan for like under $300USD plus shipping) which seems like a no brainer to just do along with the next fluid change.

I know there are plenty of people here who have scrapped the AHC system (and gone either Eibach or even Dobinsons. I totally understand why, and I had even considered that. BUT this factory system is so buttery smooth and it's a daily driver as well as doubling as a fairweather overland/camping vehicle, so for us it was the better choice.

 

[Jordan345]

I am in the interior of bc and have a 2013 lx. My truck stopped raising as well and I had diagnosed it down to moving the height sensors too much and it stopped working all together. Through my diagnosis I actually took the pump off thinking it just quit working and as a precaution during troubleshooting ordered a new one from part souq- delivered in 5 days for 900 all in approx from Dubai. Been using them for all my cruisers, from 100 series to hzj77, to my ISF. Always reliable and good prices. Anyways, I bench tested the pump and it was so anemic. Like the motor was barely turning. I took it apart as I had the new one anyways to throw in (at this point I didn’t figure out the sensor was the issue yet, but the pump was a problem anyway) and there was so much outer corrosion that the inside must have been bad. Well, it was terrible inside. So much corrosion I was surprised it was even working at all. For fun I cleaned it up and refreshed it as best I could at home and buttoned it back up and worked again on the bench. Now, I tossed it anyways as the new one was ready to go. I eventually sorted the sensors and put it back to factory and after plugging the pump back in it was good as new after flushing new fluid and replacing globes.

Best suspension option by far in my opinion and experience. First suspension part failure in 220k km and I had flushed the fluid when I bought it at 185k km. Globes at 220k km w this service. Pretty cheap imo. Tows a 9 pound boat around the marina when moving it, self levels the hitch weight, raises and lowers at speed as needed, rides better than anything else and hydraulics react proactively to loading. It’s seriously amazing kit. I have no intention of swapping it and will just keep maintaining. A little worried for when I need to replace the rear hydraulic line as I do my own work but I am sure I will figure it out. Glad you sorted it out. No point in going backwards and taking oem kit out for regular suspension when this has so much capability.

 

[arbetrader]

I am in the interior of bc and have a 2013 lx. My truck stopped raising as well and I had diagnosed it down to moving the height sensors too much and it stopped working all together. Through my diagnosis I actually took the pump off thinking it just quit working and as a precaution during troubleshooting ordered a new one from part souq- delivered in 5 days for 900 all in approx from Dubai. Been using them for all my cruisers, from 100 series to hzj77, to my ISF. Always reliable and good prices. Anyways, I bench tested the pump and it was so anemic. Like the motor was barely turning. I took it apart as I had the new one anyways to throw in (at this point I didn’t figure out the sensor was the issue yet, but the pump was a problem anyway) and there was so much outer corrosion that the inside must have been bad. Well, it was terrible inside. So much corrosion I was surprised it was even working at all. For fun I cleaned it up and refreshed it as best I could at home and buttoned it back up and worked again on the bench. Now, I tossed it anyways as the new one was ready to go. I eventually sorted the sensors and put it back to factory and after plugging the pump back in it was good as new after flushing new fluid and replacing globes.

Best suspension option by far in my opinion and experience. First suspension part failure in 220k km and I had flushed the fluid when I bought it at 185k km. Globes at 220k km w this service. Pretty cheap imo. Tows a 9 pound boat around the marina when moving it, self levels the hitch weight, raises and lowers at speed as needed, rides better than anything else and hydraulics react proactively to loading. It’s seriously amazing kit. I have no intention of swapping it and will just keep maintaining. A little worried for when I need to replace the rear hydraulic line as I do my own work but I am sure I will figure it out. Glad you sorted it out. No point in going backwards and taking oem kit out for regular suspension when this has so much capability.

Yes, if you have the knowledge and tools, it's not bad at all. My globes seem fine right now, and as I mentioned earlier the ride is better than when I first purchased it back when it had 135km; but I will likely replace them with new at the time of the next fluid swap. I'll have to check out part souq - it's great to have reasonably priced offshore choices when it comes to these parts that are otherwise so expensive purchasing locally here.

 

[AZLX570]

If you don't mind me asking, how bad is the corrosion/rust underneath your LX?

Honestly, after reading how much you paid, doesn't seem that bad at all price wise (even though they seemed to cut you a deal). Thanks for sharing and documenting.

 

[Jordan345]

Yes, if you have the knowledge and tools, it's not bad at all. My globes seem fine right now, and as I mentioned earlier the ride is better than when I first purchased it back when it had 135km; but I will likely replace them with new at the time of the next fluid swap. I'll have to check out part souq - it's great to have reasonably priced offshore choices when it comes to these parts that are otherwise so expensive purchasing locally here.

The other good source is amayama - they can be cheaper as they price from Japan. However, part souq has been able to deliver consistently and quickly and considerably cheaper than Toyota Lexus anywhere in North America, save for a few random times.

I am no mechanic but lots of experience from years of having to be self reliant in 3rd world countries. It’s all possible- we all have hands while tools are an investment that pay back over and over again. Worse case, money can fix anything if you make a mistake.

 

[linuxgod]

Hey, yeah it's no problem. My repair cost $$$$ because of corroded lines etc, and there was much extra diag time, they were trying to locate additional leaks, and ensure some lines wouldn't cause future problems - IE they had to removed the exhaust and repair a few exhaust related items with it as well.


Sooo... Here's what was originally quoted (NOTE ALL In CDN funds - USD likely will be LESS).

The original diagnosis took longer (more like 3hrs) - they charged me $500(ish) CDN after tax for this, due to the motor still making sounds but they couldn't pinpoint the actual issue until further investigation. The FSM has additional steps in sequence to check in case the answer isn't obvious.

Once the diagnosis was done (that the pump failed and needed replacement), they quoted me 2.4hrs labor for the full replacement including refilling with all new AHC fluid and bleeding the system. $432 CDN.

The part itself (pump) was quoted $4779.31 CDN at the dealer. Obviously I didn't get it there. I ended up paying $1200(ish) after exchange fees for brand new factory sealed pump from JDM planet in Japan. Note: I'll never deal with JDM Planet again due to a mistake they made, unwilling to correct it, cost me $$ (it was THEIR mistake and they refused to reimburse me).

Anyway, so that saved me $3500 on the part (CDN). Shipping was pretty quick - got the item in less than 10 days from order date.

Total cost for install with new fluid/testing/bleed (with a clean LX and minimal corrosion issues) would have been $800 (CDN)

So total diag time, $800 install, $500(ish) diag, and $1200 part = $2500.

But I needed a bunch of new lines, exhaust components, AHC pump mount kit, blah blah, and 12hrs total time = double that price.

It was worth it.

The ride is so much better than even when I bought it (as you guys all know). In the end I'm happy, and if it lasts another 5 years like this prior to new globes that's okay with me. It's worth it for the benefits of this advanced suspension system

I paid about $4000 for a higher end suspension on my LC (BP51, adjustable upper control arms). $5k isn’t awful for a luxury suspension, and you’re will likely last twice as long as mine

 

[GordJ]

That’s great news about Regency and your pump. I am in Langley and was going to Open Road Toyota in Abby for a while but they were/are “not fully satisfying” and Open Road Lexus in Port Moody left me “meh” so it is great to have an alternative that is competent. And I am considering getting an insurance pump now too.

 

[arbetrader]

I paid about $4000 for a higher end suspension on my LC (BP51, adjustable upper control arms). $5k isn’t awful for a luxury suspension, and you’re will likely last twice as long as mine

Yeah, in total that was close to $5k CDN, but that also included all the diagnistic time by 2 mechanic shops (lexus and alt shop); so I figure if my system didn't have so much rust, the total bill (including everything) would have been almost half that, which isn't at all unreasonable to me given the age of my vehicle (2008) with almost 130k miles.

 

[200 series]

Slightly unrelated here (tell me if I should post a new thread), but my 2018 AHC system is noticeably lower on the front-driver side only when dropped down to the low entry-access height. In normal height, it visually looks level, although I haven't measured with tape measure yet. Is this normal?

 

[Jordan345]

Slightly unrelated here (tell me if I should post a new thread), but my 2018 AHC system is noticeably lower on the front-driver side only when dropped down to the low entry-access height. In normal height, it visually looks level, although I haven't measured with tape measure yet. Is this normal?

You may be able to physically adjust the limit sensor, which requires you to compare the two sides, perhaps one of the nut slipped in the channel and it’s sitting oddly. You can also adjust using the tech stream - I believe each side can be adjusted and you can zero out the system. I haven’t done this but many have and it a documented process from Lexus.