Disabling the AHC and AVS systems, no warning lights. (4 Viewers)

[grinchy]

Good work being done here!

 

[JohnJB]

I'm probably going to remove the front sway bar and leave the rear. If there is too much body roll, I'll put the stock one back on. If there is still too much, I'll put a Tundra one on.

Are you going to relocate the rear bar for greater rear ground clearance?

I believe you can also relocate the rear shock mounts for better articulation, at minimum on the axle side. But odds are, you already know this! Look forward to your progress.

 

[OregonLC]

Amazing find! If this works long-term it will really open the market to LX570s.

 

[tincan45]

Interesting thread. Don't go throwing all those AHC components away! Would love to have a few spare parts hanging around. Especially interested if guys with later model LX's start doing this.

 

[turbo8]

Ran a scan on carista, got a U0132 fault code.

"Lost communication with suspension control module A"

I don't think this will show up on the dashboard.

I also had another code relating to my ventilated seat. No light ever came on for this.

 

[OregonLC]

I'd be curious to verify that VSC is still operating. Maybe get a little naughty on gravel to confirm it still intervenes? In theory, VSC would need to know what's going on with the suspension to properly correct.

 

[turbo8]

I'd be curious to verify that VSC is still operating. Maybe get a little naughty on gravel to confirm it still intervenes? In theory, VSC would need to know what's going on with the suspension to properly correct.

Correct me if I'm wrong but I was under the impression that VSC used these sensors to determine braking force:
Steering wheel angle sensor
Yaw rate sensor
Lateral acceleration sensor
Wheel speed sensor

I'm still happy to try it out though, possibly tomorrow.

 

[OregonLC]

You could be very well correct. My thought was that above 19 mph the system reverts to normal so as to protect the highway performance envelope. Without VSC able to confirm that the ride height is at normal I would have thought it would error out.

 

[turbo8]

I was thinking that too, I took it up to 60mph the other day without any errors on the dash.
I agree that it needs to be tested out correctly. Hopefully the two members that removed the stock suspension will try this out soon.

 

[bloc]

You could be very well correct. My thought was that above 19 mph the system reverts to normal so as to protect the highway performance envelope. Without VSC able to confirm that the ride height is at normal I would have thought it would error out.

With the AHC system in complete control of ride height and able to make your dash turn into a Christmas tree if it doesn’t respond as expected, or not get a speed signal into the AHC brain, communication with VSC seems unnecessary. Especially when they can use the exact same VSC system on the landcruiser without AHC and save development costs.

But that’s just speculation.

 

[cruiseroutfit]

Swaybar can be resolved a few different ways. We've got traditional sway bars (non-KDSS) on the Canguro 200 (started life as LX570)

 

[slowpok3]

Market value of poorly maintained LX570s just increased...

 

[sleeoffroad]

Ran a scan on carista, got a U0132 fault code.

"Lost communication with suspension control module A"

Not sure if this is a multiple trip code that might eventually show up. If this works, it would be great, however from reading on how AHC interacts with stability control, we were never able to figure out what feedback the ECU needs when the truck goes into a skid and it tries to manipulate the AHC and then don't get the response.

 

[hdj105]

Gave this a go today, disconnected battery, disconnected all 3 connectors to the AHC ecu, left it 10 minutes, reconnected battery and fired it up. I get the AFS OFF light flashing on the dash, no others apparent although I didn’t drive it.

I’ll need to fire up my Techstream and check for codes when I get time.

G’day Christo, I fear you’ll be correct. :-(

 

[turbo8]

Gave this a go today, disconnected battery, disconnected all 3 connectors to the AHC ecu, left it 10 minutes, reconnected battery and fired it up. I get the AFS OFF light flashing on the dash, no others apparent although I didn’t drive it.

I’ll need to fire up my Techstream and check for codes when I get time.

G’day Christo, I fear you’ll be correct. :-(

Pull the afs fuse in the passenger compartment and the afs light will go away.

 

[turbo8]

Did a test while everything is disabled. I was trying to get the traction\stability control to beep and intervene while doings some maneuvers on a dirt road. It worked and tried to correct the situation, or do whatever it is suppose to do? I also did some panic braking, abs still works.

All lights are still off!
I still have the internal U0132 fault code, but that's it.

 

[Rockdaground]

Wow y’all are on to something.

 

[CJ3Flyer]

I agee with a previous post, the value of a used LX just went up...

 

[hdj105]

Ok, another go tonight. Removed the AFS fuse, that seemingly the light. Then removed the 2 AHC fuses, ended up with yellow triangle warning light and message “CHECK AHB SYSTEM”. No mention of AHB in the owners manual, but google says it’s the auto high beam system.

The RHS fuse box is a prick to access (on RH drive vehicles) with the hood and fuel latch cables passing by!

 

[mcschreddy]

Today I attempted the first steps into getting rid of the AHC/AVS systems, I think I was successful. I still need to do some more testing to make sure warning lights don't come on, like taking out the shocks.

Here is what I did:
Put vehicle in low mode(didn't know what was going to happen, so I figured this was the safest setting to be in)
Disconnect the battery
Pulled the AHC relay in the engine compartment fuse box.
Pulled 2 ACH fuses and 1 AFS fuse from the passenger side fuse box.
Disconnected the AHC ecu in the back of the vehicle.
Waited 30 min.
Reconnected the battery.

The little lcd screen no longer shows the vehicle height position and no warning lights. The AHC/AVS levers and the off button don't do anything nor do the lights come on when toggled.

I drove it around the block up to 25mph without any warning lights. I was checking to see if it would try to raise itself up and throw an error.

I then disconnected the battery and put everything back together. All systems functioned as normal.

If @Wotan or @bacalis would like to try this and verify it works that would be great.

View attachment 2094830

I,m very interested in finding a way to get around the on board computer of the LX570. I found out the hard way about the on board computer. If someone were to ask me what I thought the LX570 was lacking clearance in the rear. I have this area that’s only 10 minutes from my house and the LX failed miserably. I went to last and the very first vender I talked with told me it wasn,t a problem to add an after market suspension system on my LX570. I must have asked him 10 times if he was positive? After I paid almost $15,000 for a great system I was told by the shop that the computer will not allow you to add after market shocks and springs. I don,t claim to know the terms of parts that make up the suspension which is terrible for someone that has logged more than 40 years of off-roading to the most remote places I could find. Lucky would be an understatement. I would like to share with you guys what I was able to get done and hopefully it can help you reach your goal with your LX570? I have to find the receipt from the shop that did the work.