AHC Problems immediately after Dealer Flush (1 Viewer)

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I’m curious. Why not just suck the fluid out of the reservoir and swap with clean fluid? I know its a shortcut, but if it remove 90% of the old fluid, wouldn’t that be good?

I know this doesn’t help op, but I’m thinking of servicing mine at 75k.

OP, is Lexus going to cover the pump?
The AHC system does not "recirculate" fluid, so you will still have old fluid in all of the components that actually use it.
 
All very good Intel!!! I'd definitely hold dealer responsible for all repairs, parts and rental fess. All you have to do is threaten to file judgment and they will jump through your hoops! I took my cv's to dealer to have my mid-shaft swapped for a longer one with new boot kits. See in the photo what they tried to give me back. Looks like a ***ing wolverine knarlled on it. Needless to say I refused. And he seemed very a matter of fact making excuses. Afyer speaking with high up and threatening to sue.... that i brought it to lexus cause i expect perfection....They replaced the housings and all dust shields and seals. Trust me not a judge in the country wouldn't see it your way!!!
 
Un acceptable!!!!

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The AHC system does not "recirculate" fluid, so you will still have old fluid in all of the components that actually use it.
Then what is the reservoir for? If you drop truck in low, suck all fluid out, add new fluid, and then run it form high to low 5 times, I bet a lot of fluid moves around. I would hate to pay a dealer to do this, and then my truck breaks, and preventative maintenance leads to a 3k repair Bill.
Not arguing, just curious.
 
I'm with Tacoduck.

OP, what dealer was this in Denver? So I know what I'm up against if I go to them.
 
Then what is the reservoir for? If you drop truck in low, suck all fluid out, add new fluid, and then run it form high to low 5 times, I bet a lot of fluid moves around. I would hate to pay a dealer to do this, and then my truck breaks, and preventative maintenance leads to a 3k repair Bill.
Not arguing, just curious.

The reservoir provides fluid for the lines (when they need more), and a place to store fluid (when they need less).

Fluid will move back/forth along the lines, but it will not fully recirculate through the lines and components on those lines. A full flush is the way to do it properly.
 
Be sure that you file a complaint with Lexus corporate. PM if you need the number. I recently went through a terrible experience where they had my car for a total of 15 days waiting for parts and approval from lexus field support to replace. Lexus ended up writing me a check for lost time.

I also had a need to tow - so the dealer was able to give me a GX.

Good luck.
 
So now the Dealer is saying that a pump will not be available till August!!!!! WTF am I supposed to do without a truck for months? This is beyond anything I could of dreamed of, total s*** show.
 
So now the Dealer is saying that a pump will not be available till August!!!!! WTF am I supposed to do without a truck for months? This is beyond anything I could of dreamed of, total s*** show.


They need to supply you a loaner or pay for your rental.... if they dont.... pay 65$ to file a judgment.... I promise you they know a judge will see it your way and settle out of court
 
So now the Dealer is saying that a pump will not be available till August!!!!! WTF am I supposed to do without a truck for months? This is beyond anything I could of dreamed of, total s*** show.
I have @turbo8 old pump and reservoir assembly on a shelf. send me a PM if you want a used option.
 
Get your rig back from the dealer. It will operate fine w/o functioning AHC (ride may suck, but it will still drive down the road). Buy 5 bottles of AHC fluid. Bleed the accumulator several times; if the bled fluid looks fresh, recycle it rather than cracking open new AHC fluid bottles.

I had a similar issue on my Hundy; trapped air is trapped air on both AHC flavors.

There should also be steps in the FSM to hotwire the AHC pump to ensure the pump is OK. Trust but verify (yourself) the diagnosis from the dealer.

Optimal time to get a copy of Techstream and learn to service the AHC yourself. Don't be shy about following the trails that the Hundy crowd blazed along the way.

For a local Denver area AHC wizard, look up @suprarx7nut and see if he could help. He's good people.
 
Thanks for your comments. Just FYI, I have had and built several LC/LX’s and I ripped out the AHC on two 100’s. Hell, I just took a saw to my Lx putting on Dissent bumpers, so I’m not afraid to get in there and deal with this myself, but at this point the fault is entirely on the dealer. I’m afraid if I get it back that then all responsibility falls on me. But I might have to because the current situation is unbelievable!
Today I filed an official complaint case with Lexus and I will hear back from my case manager tomorrow. I also drafted a detailed letter that I plan on sending to several folks at the dealer tomorrow after I talk with corporate.
I’m actually amazed at how absolutely pissed off I am at this. I’m a pretty calm guy and I can’t stop thinking about how pissed I am. I also didn’t realize how much of my life isn’t possible without my truck. I nearly live out of the thing. Today I picked up the CEO of a medical device company (my full time job is in sales of medical devices) and I felt like a little bitch in this Lexus NX. ****!
Not to mention I spend ALL my free time (already have over 20 days and the season hasn’t really started) on the river either guiding or for recreation and I literally can’t do anything I have planned for the summer without my truck. I’m even considering buying an 80 series just to get by, but why should I have to spend my money to fix their mistakes.

I just need KUNI Lexus in Denver to step up and make it right.
 
I have made it very clear that I need a bigger car that can tow. Apparently the RX is all I can get. I don’t know what to do, I’m borrowing my brothers LC 100 this week, but I don’t know what I’ll do after that
I would ask to speak to the general manager and if they're not in, insist on calling their cell and home phone.

Not sure how new your rig is, but it's completely unacceptable to put an LX owner in an RX and shrug it off.

Tell them to go strip a pump off one of the new models on the lot if they can't reprime the one in your car.
Hmmm…”…We've got a pump on order just so that our name is on the list because as I mentioned before they are on a national backorder. It seems to be a common problem for these to go bad.”

Is this true?! These pumps go bad so frequently?
Not to "our" knowledge. Those things are incredibly robust.
So now the Dealer is saying that a pump will not be available till August!!!!! WTF am I supposed to do without a truck for months? This is beyond anything I could of dreamed of, total s*** show.
I would tell them to get a no cost trade in started on a new LX. You've got huge leverage here. They failed a basic maintenance task that they think ruined your vehicle.

I'm sure it's just a little trapped air. I'm not familiar with the 200 system, but on the 100 you will absolutely get that fault code if you have air. It absolutely does not mean a failed pump. The ECU is counting on hydraulic pressure increases. If air is present the pressure increase is exponentially different and it will register as essentially zero increase. Hence, the code.

If I was more familiar with the 200, I'd say come by the shop, but I'm not... Yet.
 
I would ask to speak to the general manager and if they're not in, insist on calling their cell and home phone.

Not sure how new your rig is, but it's completely unacceptable to put an LX owner in an RX and shrug it off.

Tell them to go strip a pump off one of the new models on the lot if they can't reprime the one in your car.

Not to "our" knowledge. Those things are incredibly robust.

I would tell them to get a no cost trade in started on a new LX. You've got huge leverage here. They failed a basic maintenance task that they think ruined your vehicle.

I'm sure it's just a little trapped air. I'm not familiar with the 200 system, but on the 100 you will absolutely get that fault code if you have air. It absolutely does not mean a failed pump. The ECU is counting on hydraulic pressure increases. If air is present the pressure increase is exponentially different and it will register as essentially zero increase. Hence, the code.

If I was more familiar with the 200, I'd say come by the shop, but I'm not... Yet.
A no cost trade on a lx570? Let me know how that goes.
 
A no cost trade on a lx570? Let me know how that goes.
If my ~$60-70k used vehicle was rendered inoperable by a dealer for 3-4 months I don't think that's an unreasonable place to start negotiations.

At the very least an LX loaner for the duration of the downtime should be on the table. In cases like this the dealer has a wealth of options and pressure from Lexus USA can make an awful lot happen. On the scale from nothing (where OP seems to be now) to a no-cost trade on a new LX, I bet it's possible to land closer to the new LX than nothing.

Or... they could read up on how to prime the AHC pump/system and probably get that existing pump to generate some hydraulic pressure. I doubt the pump is the problem, but if they insist it is, I'd switch over to negotiating how to be made whole promptly.
 
Hopefully this is your issue. It shouldn't be too hard to solve, and it's a matter of bleeding the right nipple at the control pump accumulator so the AHC pump is no longer dead-heading against high-pressure to prime again.

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So I added a little more fluid to the reservoir, but in in L and bled maybe 100ml off the control pump accumulator then 100-120ml off each corner. Started it up, then pump was making a super high pitched whining noise and wouldn’t move the car at all. Shut it off, checked the fluid level in the res and it hadn’t gone down at all, odd. Bled another 100ish ml off each corner, opened the valve on the accumulator too but nothing came out😬 Most definitely got some air bubbles that second time coming out in the also very clean fluid. Started the car up, pump wouldn’t kick on at all and the trouble code would pop up on the display almost immediately, whereas before the code would come on after the startup sequence probably 30+ seconds after startup. I’m guessing I’ll have to get one of those scanny tools that lets you manually cycle the pump on now that I’ve seen mentioned, but what should my next move be with that? Isn’t it weird that the fluid level in the reservoir remained high after draining like 800-900ml of fluid, yeah? Especially with the vehicle remaining in L the whole time...
 
Ugh, sorry to hear this. Several wks ago I had my 60k/AHC fluid swap/fuel pump recall done at Kuni as I live so close. All appears ok but stories like this make me to want look elsewhere. You should be in a RX at minimum...had one for a few days. If you find a spare min, can you pm me name of tech and service advisor as I'd request to avoid them.
 
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So I added a little more fluid to the reservoir, but in in L and bled maybe 100ml off the control pump accumulator then 100-120ml off each corner. Started it up, then pump was making a super high pitched whining noise and wouldn’t move the car at all. Shut it off, checked the fluid level in the res and it hadn’t gone down at all, odd. Bled another 100ish ml off each corner, opened the valve on the accumulator too but nothing came out😬 Most definitely got some air bubbles that second time coming out in the also very clean fluid. Started the car up, pump wouldn’t kick on at all and the trouble code would pop up on the display almost immediately, whereas before the code would come on after the startup sequence probably 30+ seconds after startup. I’m guessing I’ll have to get one of those scanny tools that lets you manually cycle the pump on now that I’ve seen mentioned, but what should my next move be with that? Isn’t it weird that the fluid level in the reservoir remained high after draining like 800-900ml of fluid, yeah? Especially with the vehicle remaining in L the whole time...

This is probably the same thing that the OP dealer is having trouble with. The FSM really doesn't offer much guidance or recourse here for non-priming. I'm almost wondering if the issue is not air not from letting the reservoir run low, but maybe air pushed into the pump from the pressurized side of the system (when going into AHC low) causing the pump to air lock? Or hope that contaminants did not get in and plug the draw line.

Either way, it's a matter of pulling fluid through the pump again, and I know it's more difficult than just typing it.

If the pump doesn't run when you want it to, you can directly power it, but that can be tricky too. Hope @tbisaacs strategy can work? If you must manually do this:

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If that doesn't work, you may need to get creative powering the pump manually and one of the following in order of difficulty
1) Bleed the system completely down, both at the pump accumulator (which you have already done), and the suspension globes. Any remaining pressure is going to continue to keep the AHC pump dead heading
2) Use a brake bleeder vacuum pump like a Mityvac to draw vacuum on the system to help prime the pump
3) Disconnect or open connection #6 height control tube on high pressure output side of the AHC pump to allow it to prime. Probably easier to disconnect at the control valve assembly side (next to the pump accumulator)

Here's some additional hints from the FSM, but nothing you haven't been doing.

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Tell the dealer to pay for a pickup truck rental. My dealer was offering to do just that when I needed to tow and they were dealing with the AHC issues they caused.
 

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