LX570 AHC Globe/Accumulator Replacement (6 Viewers)

[NKP Garage]

Hey all. Had some issues with my globe replacement and could use some help/advice.

We bled all 4 globes down
Swapped all globes
Topped up fluid in reservoir
Started truck.
Multiple time trying to get vehicle up. Took a long time but finally moved up. Got into high but wasn’t behaving like normal.
Fluid was always kept in reservoir above
Min.
In a few occasions we lowered the truck and it dropped sorta normal.
Now the “check ahc surtem” code is up and won’t let me lift eh truck.
Truck is low low.
Bled all corners down to try and get back to square 1
Still won’t let me. Just shows the error message and that’s about it.

I’m betting the code is set and won’t clear? No pump action at all now.

Next steps ??

Try continuously flipping the switch to the UP position over and over while starting the truck, and keep flipping it up to the up position until it starts flashing UP. Then just let it sit idling for 10 minutes.

 

[arnott1t]

ok I'll give that a go.... I'd been doing that and it would read "upP for a second and then go to "lo" and show the error code. won't stay displaying the up

 

[lx200inAR]

ok I'll give that a go.... I'd been doing that and it would read "upP for a second and then go to "lo" and show the error code. won't stay displaying the up

As long as you don't have the AHC warning, the truck will eventually work out getting it to the proper height. The display won't show you that it's doing anything, but if you monitor the pump, you will see that it cycles on and off periodically to get the truck back up to height. This can be seen if you monitor the AHC ECU in Techstream as well. Which is where the suggestion above about letting it idle for a while comes from. I'd stop bleeding but continue to make sure you have enough fluid. Bleeding is just making more work for the pump again.

 

[arnott1t]

for sure... its just my pump isn't running and won't run now....

for the first while it was running and getting the vehicle up but now won't run at all. not at start up and not after running for 5-10mins... I'll try letting it sit again. I feel like I triggered an error code in the AHC ECU and it locking out the pump but i'm only guessing....

Looking into getting techstream now... which doesn't seem super easy.

Also picking up a friends fancy diagnostic tool hoping it can maybe clear the code.. Autel MK808

 

[highfructose]

for sure... its just my pump isn't running and won't run now....

for the first while it was running and getting the vehicle up but now won't run at all. not at start up and not after running for 5-10mins... I'll try letting it sit again. I feel like I triggered an error code in the AHC ECU and it locking out the pump but i'm only guessing....

Looking into getting techstream now... which doesn't seem super easy.

Also picking up a friends fancy diagnostic tool hoping it can maybe clear the code.. Autel MK808

If you have an old windows laptop, the techstream program is free, the cable is like $15-$35 depending on where you buy

 

[trudd]

Sorry to hear of your troubles @arnott1t.

I'll be replacing my globes soon. Did this on my old LX a year ago, but I've already forgotten best practice...

Is it best to bleed and swap one globe at a time, start the car so it levels out, and then move on to the next corner? Seems like that approach may avoid wigging out the system?

 

[lx200inAR]

Sorry to hear of your troubles @arnott1t.

I'll be replacing my globes soon. Did this on my old LX a year ago, but I've already forgotten best practice...

Is it best to bleed and swap one globe at a time, start the car so it levels out, and then move on to the next corner? Seems like that approach may avoid wigging out the system?

This is how I did it, and how I recommend it be done. Seems like once a month we get this same post about someone who did all 4 at once and are having trouble getting the truck back to N.

Not saying it can't work doing all 4 at a time, just that I think it recovers quicker if you do one at a time and gives you better feeling about how it's going. Also, order of operations wise, there's no reason you can't do them individually.

 

[lx200inAR]

for sure... its just my pump isn't running and won't run now....

for the first while it was running and getting the vehicle up but now won't run at all. not at start up and not after running for 5-10mins... I'll try letting it sit again. I feel like I triggered an error code in the AHC ECU and it locking out the pump but i'm only guessing....

Looking into getting techstream now... which doesn't seem super easy.

Also picking up a friends fancy diagnostic tool hoping it can maybe clear the code.. Autel MK808

You can try disconnecting battery for a while (20-30min) to get code to clear. OBD Fusion (with extended Lexus pack) / standard Bluetooth OBDII tool might be able to clear the AHC DTC. It can definitely talk to the AHC ECU, just not sure if it can clear codes.

One other tip i can offer, and this isn't really scientific and may not be the right way to do it, so consider at your own risk. The times I've had to get the truck back after lowering all 4 corners to bumps doing bleeding, I've found that pulling the fill valve to the reservoir while it is doing the initial lift can help. The fill valve seems to be a check valve and you end up with a vacuum in the reservoir that works against the pump pulling fluid into the system.

 

[grinchy]

The pump not running at all could be a fuse maybe?

 

[radman]

swap one globe at a time, start the car so it levels out, and then move on to the next corner?

jackpot.

 

[chriscosta416]

ok I'll give that a go.... I'd been doing that and it would read "upP for a second and then go to "lo" and show the error code. won't stay displaying the up

Are you in SoCal? If so I have Techstream and can stop by and try a few things.

More than likely you have stuck actuator.

Tech stream can manually activate the actuator to free it up.

Do you hear the pump kick on?

 

[arnott1t]

Ok so did some more diagnostic and it isn’t looking good.

Using the Autel I can connect to ahc module. Read codes thay said abnormal pump pressure. Clear the code and it comes right back.

Did that many times.

Then manually turned on pump with tool. Nothing happened. No oump action. Relay turns on.

Checked relay. Has power feeding and get signal to close.

Checked power to pump. Get power when told.

Pump is siezed/broken/bad somehow all of a sudden.

Now to read about removal…

 

[paulunm]

You didn't happen to use black 1 liter plastic containers of AHC fluid did you?

That could plug up the filters on the pump...

If not, keep the cap off of the reservoir and maybe the filter out of the neck while trying all of this. Cap can create a vacuum in the reservoir. Keep flicking the Up button when you start the engine.

 

[radman]

Then manually turned on pump with tool. Nothing happened. No oump action. Relay turns on.

you can get a 12v SLA or car battery and connect directly to the pump. Some guys have even run the pump in reverse for a few seconds to get it to prime.

 

[arnott1t]

Here was tonight’s adventure.

Hooked pump in reverse. Nothing

Hooked pump in normal. Turn on with scan tool and hit pump with hammer. It ran! Sounded bad… made no pressure.

Pulled pump. Absolute nightmare for rusty trucks like mine. Not fun

Tons of debris and s*** in tank and pump.

In process of cleaning the replacing….

Fingers crossed tomorrow.


I did use small plastic bottles

 

[arnott1t]

Looks like the alum sleeve on pump mount was spalling a little? Not sure where else this came from.

 

[grinchy]

There are very tiny filters in the pump inlet , likely these are also clogged.

The issue with the 1L plastic bottles is they could put a gel like material into the tank that clogged the tiny filters in the pump.

The pump is not self priming so after you take it apart and clean it and put it back together definitely have a priming plan.

And great work getting this thing out and working the problem!

 

[paulunm]

Here was tonight’s adventure.

Hooked pump in reverse. Nothing

Hooked pump in normal. Turn on with scan tool and hit pump with hammer. It ran! Sounded bad… made no pressure.

Pulled pump. Absolute nightmare for rusty trucks like mine. Not fun

Tons of debris and s*** in tank and pump.

In process of cleaning the replacing….

Fingers crossed tomorrow.


I did use small plastic bottles

Oh no... well make sure you get the 2.5L cans, toss the bottles.

 

[lx200inAR]

A few users have tried cleaning the pumps. I don't think anyone has separated the two pump halves and gotten it back together properly. If it were me, I'd try to clean the screens without separating the pump and see if I could get it running that way.
This thread has a lot of details...although looks like some of the pictures/videos may be gone now.

AHC Pump Fun - Disassembly and Clean - Verbose Edition

forum.ih8mud.com

And one more, (this one has some good links to other posts as well)

HELP! AHC Pump Issue After Reservoir Drain/Refill

Hello Cruiser gurus! I'm having an AHC issue on a new-to-me 2008 LX With no history of AHC service from Lexus I decided to flush AHC... didn't seem like too big of a deal from the reading I did :) I dropped AHC into LOW mode, checked the reservoir (which didn't much fluid in it), drained the...

forum.ih8mud.com

 

[32cls6speedmt]

If pump can’t be repaired then a brand new pump can be purchased.

TOYOTA Genuine Land Cruiser 200 Lexus LX570 AHC Height Control Pump Motor | JDM Planet

jdm-planet.com