AHC won't go up or down (2 Viewers)

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Yeah. Look under your hood. There is a small box that looks almost like fuse box on the passenger side fender. Take the cap off and you will see a bunch of holes and the cap will tell you which hole is which. Then follow PADO's instructions on shorting/brake pedal tapping.

Should work after that hopefully.
OK thanks I will try this after work, fingers crossed!!
 
one more suggestion, check your battery voltage, the AHC is the first this to stop working if your alternator, battery, charging system as a whole has issues, because it requires a full charge on the battery to operate. it looks like your problem is solved, but should it happen again in the next couple of days, it's probably somthing in the charging system...
 
one more suggestion, check your battery voltage, the AHC is the first this to stop working if your alternator, battery, charging system as a whole has issues, because it requires a full charge on the battery to operate. it looks like your problem is solved, but should it happen again in the next couple of days, it's probably somthing in the charging system...
Ok thanks for the help, I do have both a new Toyota battery and Toyota alternator (replaced a month ago) so I hope I'm good there!
 
mine was doing the same thing as the OP's over the weekend after a trip with some minor wheeling, but a lot of rain. i suspect there was a short at some point just b/c of all the humidity. worked fine until i got in the driveway back at the house. wouldn't go up or down. figured i'd leave it in the "N" position and come here to look for a solution. before i got here, after driving around a little bit, it started working again.
*i have the slee override too
 
I think the issue is no casing or potting on the override. It really needs some form of protection from shorting. I haven't reinstalled mine because I found I really don't need it, but if I were to reinstall it, I would either wrap the hell out of it with electrical tape or try and find a plastic box that it could fit in.
 
Can you open the trouble code page? The top blue tab on the left, the codes should be listed there. Make a note of them and then clear them with the little engine/eraser symbol towards the bottom of the screen. It will ask for confirmation etc. If that doesn't work try a manual clear: ignition off, short Tc and E1 in dlc1, ignition on and push brake pedal 9 times in less than 3 seconds. IG off, remove short. Hopefully one of these methods works, but I've had a DTC C1743 that wouldn't clear either way and it wasn't until I pulled the 20A AHC IG fuse the ECU recovered itself.
Nothing really jumps off your screen shot as being out of whack, pressure sensor fields didn't all populate but that happens.
The rear gate valve is the one that connects/disconnects your rear wheels' hydraulically. It's probably fine and not a concern at the moment.
You can install someone's pre loved AHC ECU if they've done a delete without it introducing any new issues for them -beyond not having the designed inputs to vgrs, ABS/VSC ECUs.

Wow... Awesome!
 
If any of you guys know how to run 3D CAD I have a couple 3D printers and could print the box pretty easily. I've got enough short pieces of filament left over that I'd do it for the equivalent of shipping. I've considered ordering one of these over rides as well but just haven't gotten to it so I am not able to take measurements and scab something together. I also have no CAD skills. I am willing to print though...
 
I think the issue is no casing or potting on the override. It really needs some form of protection from shorting. I haven't reinstalled mine because I found I really don't need it, but if I were to reinstall it, I would either wrap the hell out of it with electrical tape or try and find a plastic box that it could fit in.
I agree, I am going to get back in there and wrap the hell out of it with electrical tape to see if it solves the problem. Also, got to work this morning and tried to put it in H and low-and-behold it worked without me doing anything to it last night. Must be a short somewhere, but where? I am also pretty disappointed with the switch being so mount un-friendly. It would be nice if there was a flat front for some double-sided tape or a switch that incorporated threads for a ring screw type mount for installing on a blank... I actually ended up adding some wire to all the leads so I wasn't having to tug the :censor: out of it to reach the blank on the left side of steering column.
 
Looking at the easily available pictures (the install instructions), it looks to me like someone with even minimal soldering experience could easily desolder the switch and the led, then you could solder wire into the card and remote mount the circuit from the switch and indicator.

I agree with you guys the design could have easily included a case, or at least a coating of polyurethane or such to insulate the card.
 
Time to call Slee and order a lift kit, LOL

It was a minor hiccup caused by lack of insulation/me not doing a good enough job insulating the override.

In all honesty, I should have never bought the override. The system works great as is.

AHC works wonderfully now and I just ordered king springs from Australia to compensate for when I get Benc's rear bumper on there. I love the AHC. I wont tear it out until its too far gone to repair.
 
It was a minor hiccup caused by lack of insulation/me not doing a good enough job insulating the override.

In all honesty, I should have never bought the override. The system works great as is.

AHC works wonderfully now and I just ordered king springs from Australia to compensate for when I get Benc's rear bumper on there. I love the AHC. I wont tear it out until its too far gone to repair.

I will be curious as to how you like the King springs!
 
They have been sitting in the garage waiting to be put on. I'm worried if I put them on before getting the bumper, it will be super bouncy. I really want to though haha

Got it!
I went the other way - put a BIO bumper on, same rear springs. We took it out to Canyonlands and wheeling it and AHC did fine. I need to get TechStream and plug in - listen to what my 470 is trying to tell me...
 
Looking at the easily available pictures (the install instructions), it looks to me like someone with even minimal soldering experience could easily desolder the switch and the led, then you could solder wire into the card and remote mount the circuit from the switch and indicator.

I agree with you guys the design could have easily included a case, or at least a coating of polyurethane or such to insulate the card.

yeah, but how much harder would it have been for slee to just soldered wire leads there instead of the switch. would have been so much cleaner of an install to be able to use a blank on the dash, or to put a clean switch instead of that odd little toggle. functionally, it does what it says, but there's no real good place to put it. i drilled 2 holes in the black surround on the gauge cluster and put it to the right of the steering column. the LED is pretty bright too.

if someone makes a box of sorts to house it, i'll chip in for one.
 
yeah, but how much harder would it have been for slee to just soldered wire leads there instead of the switch. would have been so much cleaner of an install to be able to use a blank on the dash, or to put a clean switch instead of that odd little toggle. functionally, it does what it says, but there's no real good place to put it. i drilled 2 holes in the black surround on the gauge cluster and put it to the right of the steering column. the LED is pretty bright too.

if someone makes a box of sorts to house it, i'll chip in for one.

I plan to eventually have a switch pod for lights and other accessories. I think if I get that, I would remove the led and switch from the override and run some switch wires to the pod. Tape the override super well and stuff it behind the dash somewhere.
 
Dude! You are seriously a life saver. I can't thank you enough.

My techstream doesn't let me read the codes for some reason. I constantly get an error. I assume its probably my crappy Amazon cable or software or the fact that I did a bunch of stuff to get it to work on my win 7 64-bit laptop.

Anyway, I jumped straight to shorting Tc and E1 to do a reset and it worked!!

Thank you so much man! I was about to buy the only AHC ECU on ebay for nearly $300!
Hey Rami, did you ever get the trouble codes for AHC to read? I got Techstream now, and I am having the same problem. The AHC is the main reason I got Techstream and I can't read s%&t...
 
Hey Rami, did you ever get the trouble codes for AHC to read? I got Techstream now, and I am having the same problem. The AHC is the main reason I got Techstream and I can't read s%&t...

Unfortunately I never did. I just manually reset the codes and haven't had an issue since. Wish I could help
 
Hi!
This is my first post.
First of all, my thanks to the community, and my apologizes for my poor English.

At 90k miles the rear suspension of my Land Cruiser HDJ100 was still perfect, but the front was getting harder and harder, I had 7 graduations on my AHC from Lo to Hi, I did a complete flushing: no noticeable improvement.
Then I tried many settings on the torsion bars: very small improvement.

At 100K the AHC was still able to perform Lo-N-Hi, with still 7 graduations, but I felt that some element of the system was at the end of its life, so I ordered new spheres from Pleiades (thanks to the forum).

Soon after, I noticed that my front suspension stayed lower and was really hard (I had pushed hard on the brakes several times to activate the ABS to complete the brake flush process, thanks to you 2001LC).

I saw also that the AHC wouldn’t move (N-Lo / N-Hi), I thought that the old spheres had been killed by the hard braking, so I didn’t insist.

After this I went thru PADDO’s flush method in order to put the front new spheres (thanks to you PADDO).

I flushed the front first, and put on the new front spheres.
I saw that the front was low and that the rear was very high.
When activating the Lo-N-Hi, it flashed but nothing happened.
After this a short test ride, and activating, nothing had changed.

Then I flushed the rear with PADDO’s method, and put the new rear spheres.
Lo-N-Hi still didn’t work, small test, when braking the back was flexible like driving with coils fitted with dead shocks, and the front was like riding with no shock at all…

Several activations (Lo-N-Hi not working), several tests, and several bleeds until there was no more fluid left in the system.
Several times back to fundamentals/power sources/etc.: Lo-N-Hi not working.

So came the time for the Active Test (shorting TS & E1 in Dlc1): nothing moved.
Back and forth to fundamentals/active test, nothing moved…

So I went thru the Inspection Procedure DTC C1762/62 (thank you PADDO/uHu/jymChow) :
at step 2, I saw that the electric motor was running as per procedure (positive in n°2, negative in n°1).
But, motor was also running with ONLY the connector n°2 being connected to positive, the connector n°1 BEING OT CONNECTED to negative…
Motor was running without negative connected and fluid didn’t seem to move: confusing.

After others back and forth (inspection procedure/forum), my conclusion was that the pump should be the problem.
These tests have had the merit of allowing me to see that the fluid has moved a little, a very little.

So I thought that if I put the four wheels on jacks I might have a chance to get the fluid into the system with the Inspection Procedure & Active Test.
Step 2, and yes, some fluid entered in the system!
So, Active test again one more: all the fluid (front then rear) entered in the system.

Then the truck back to the ground, the front and rear were too high: I had activated too long being focused too much on the fluid level.
I bleed slowly the front then rear in order to get the correct “N” height (front 83mm, rear 71mm).
I didn’t see any bubbles.
I took off the all the AHC fuses and relay and went for a try: it was good.

For sure, it’s very unorthodox, but it might help as a temporary backup solution for those who have to come back home from a remote place with a truck on the bumps, or for those like dwh13 who have to wait for their pump, or might complete the guru’s AHC database.

Of course I’ll order a new pump, VCI cable (Teachstream already downloaded) and will proceed to all the measurements to do the things properly.

As ordering spare parts is not so easy for me, before ordering the pump, I would like to know from those who have only changed their pump, if their electric motor failed soon after or not.

Thanks.
 
Hi!
This is my first post.
First of all, my thanks to the community, and my apologizes for my poor English.

At 90k miles the rear suspension of my Land Cruiser HDJ100 was still perfect, but the front was getting harder and harder, I had 7 graduations on my AHC from Lo to Hi, I did a complete flushing: no noticeable improvement.
Then I tried many settings on the torsion bars: very small improvement.

At 100K the AHC was still able to perform Lo-N-Hi, with still 7 graduations, but I felt that some element of the system was at the end of its life, so I ordered new spheres from Pleiades (thanks to the forum).

Soon after, I noticed that my front suspension stayed lower and was really hard (I had pushed hard on the brakes several times to activate the ABS to complete the brake flush process, thanks to you 2001LC).

I saw also that the AHC wouldn’t move (N-Lo / N-Hi), I thought that the old spheres had been killed by the hard braking, so I didn’t insist.

After this I went thru PADDO’s flush method in order to put the front new spheres (thanks to you PADDO).

I flushed the front first, and put on the new front spheres.
I saw that the front was low and that the rear was very high.
When activating the Lo-N-Hi, it flashed but nothing happened.
After this a short test ride, and activating, nothing had changed.

Then I flushed the rear with PADDO’s method, and put the new rear spheres.
Lo-N-Hi still didn’t work, small test, when braking the back was flexible like driving with coils fitted with dead shocks, and the front was like riding with no shock at all…

Several activations (Lo-N-Hi not working), several tests, and several bleeds until there was no more fluid left in the system.
Several times back to fundamentals/power sources/etc.: Lo-N-Hi not working.

So came the time for the Active Test (shorting TS & E1 in Dlc1): nothing moved.
Back and forth to fundamentals/active test, nothing moved…

So I went thru the Inspection Procedure DTC C1762/62 (thank you PADDO/uHu/jymChow) :
at step 2, I saw that the electric motor was running as per procedure (positive in n°2, negative in n°1).
But, motor was also running with ONLY the connector n°2 being connected to positive, the connector n°1 BEING OT CONNECTED to negative…
Motor was running without negative connected and fluid didn’t seem to move: confusing.

After others back and forth (inspection procedure/forum), my conclusion was that the pump should be the problem.
These tests have had the merit of allowing me to see that the fluid has moved a little, a very little.

So I thought that if I put the four wheels on jacks I might have a chance to get the fluid into the system with the Inspection Procedure & Active Test.
Step 2, and yes, some fluid entered in the system!
So, Active test again one more: all the fluid (front then rear) entered in the system.

Then the truck back to the ground, the front and rear were too high: I had activated too long being focused too much on the fluid level.
I bleed slowly the front then rear in order to get the correct “N” height (front 83mm, rear 71mm).
I didn’t see any bubbles.
I took off the all the AHC fuses and relay and went for a try: it was good.

For sure, it’s very unorthodox, but it might help as a temporary backup solution for those who have to come back home from a remote place with a truck on the bumps, or for those like dwh13 who have to wait for their pump, or might complete the guru’s AHC database.

Of course I’ll order a new pump, VCI cable (Teachstream already downloaded) and will proceed to all the measurements to do the things properly.

As ordering spare parts is not so easy for me, before ordering the pump, I would like to know from those who have only changed their pump, if their electric motor failed soon after or not.

Thanks.


So you had all 4 wheels off the ground while activating AHC? Weird and glad that it worked for you, but isn't this normally a huge no no? (According to manual and warning labels next to the center console)
 

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