AHC Help: Can't clear code (1 Viewer)

[Jcreme]

Hey fam! I just replaced my AHC globes and while bleeding and refilling the system after, the AHC threw a code 62/1762 Abnormal pump pressure. I apparently got a contaminated bottle of AHC fluid which contained a white gel (from the dealer)! I didn't notice until I started to add more and saw the reservoir screen all gummed up.

UPDATE: Do not disassemble the pump-sub assembly like I did. See my post below about what to do if you have a code 62/1762 Abnormal Pump Pressure.

I removed the pump assembly and cleaned out the pump and screens and tested the flow was not obscured by operating the pump manually. I observed the gel blockage when cleaning it, so I am certain this was blocking the inlet, throwing the code.



After reinstalling the pump assembly, the pump would not run and, although I could clear the code, it immediately triggered again.. The pump will not run in diagnosis mode for the Active Test either.

I have removed the pump and checked everything again. All good. I have not reinstalled yet. I don't suspect the pump, motor, or signal is bad, The pump was running when I took it out the first time.

The front suspension is bottomed out as I was in the process of bleeding the system. If that matters.

I have had only the one code (1762) throughout the process.

Any ideas? Thanks again!

Justin

 

[suprarx7nut]

Hey fam! I just replaced my AHC globes and while bleeding and refilling the system after, the AHC threw a code 62/1762 Abnormal pump pressure. I apparently got a contaminated bottle of AHC fluid which contained a white gel (from the dealer)! I didn't notice until I started to add more and saw the reservoir screen all gummed up.

View attachment 2867300

I removed the pump assembly and cleaned out the pump and screens and tested the flow was not obscured by operating the pump manually. I observed the gel blockage when cleaning it, so I am certain this was blocking the inlet, throwing the code.



After reinstalling the pump assembly, the pump would not run and, although I could clear the code, it immediately triggered again.. The pump will not run in diagnosis mode for the Active Test either.

I have removed the pump and checked everything again. All good. I have not reinstalled yet. I don't suspect the pump, motor, or signal is bad, The pump was running when I took it out the first time.

The front suspension is bottomed out as I was in the process of bleeding the system. If that matters.

I have had only the one code (1762) throughout the process.

Any ideas? Thanks again!

Justin

Thanks for the video. What a mess. This seems to be a pervasive issue recently.

The code for abnormal pressure, if I recall correctly, takes only a fraction of a second to trigger - I recall 0.6 seconds. The pump should produce pressure immediately. If it does not, the code triggers right away.

I would run the "active test" that forces the pump to run. I think you might just need to get the pump primed and flowing liquid.

 

[lx200inAR]

On the 200 forum, there have been at least 6 or 8 identified cases of the bad fluid. There have been 2 members who have attempted to clean their pumps, but have not been able to get them started and ended up replacing. I think they both took the pump apart and neither were sure they reassembled properly.
Hopefully you make some positive headway On that front.

Toyota replaced one of the members pumps after he showed them the fluid. I haven’t heard of anything better than getting a refund on fluid from anyone else.
On the 200 forum there have been regular instances of pump failures after fluid changes for the last year or so, whether DIY or service center fluid swaps. It’s not unfathomable that the first cases were instances of bad fluid that wasn’t recognized as such.

 

[Jcreme]

Thanks for the video. What a mess. This seems to be a pervasive issue recently.

The code for abnormal pressure, if I recall correctly, takes only a fraction of a second to trigger - I recall 0.6 seconds. The pump should produce pressure immediately. If it does not, the code triggers right away.

I would run the "active test" that forces the pump to run. I think you might just need to get the pump primed and flowing liquid.

Yes. This is where I am confused. The pump doesn’t run for the Active Test ¯\_(ツ)_/¯

 

[2001LC]

Can I ask. Where did you buy the AHC?

 

[2001LC]

I've talked with mt parts guys at Toyota, he knew nothing about bad fluid. He as did I look on our shelves, at bottles. No dates on them! So how can we tell a bad bottle form good?

So I just now called Lexus parts, which sees a lot more AHC systems. Parts guy said they got internal service notice (he thinks it was from shop forman, looking for me now). He recommends filtering fluid. I'd not want to even use filtered or not. I'm near end of a case I bought, without issue. But this is concerning.

Any info on fluid and why? Has Toyota or Lexus officially put anything out on this?

 

[lx200inAR]

This thread has the most recent info coming from 200 series guys. It says that at least some Toyota dealers are pulling the plastic bottles and are only going to sell the metal cans. No word from Toyota yet that they actually discovered a problem with the plastic containers. The metal cans were pretty hard to come by in NA, but now maybe Toyota is restocking the NA market with those cans.

I know the consensus on 200 forum is to not filter and use the fluid since we have no idea where the gel is coming from.

Post in thread 'HELP! AHC Pump Issue After Reservoir Drain/Refill'
HELP! AHC Pump Issue After Reservoir Drain/Refill - https://forum.ih8mud.com/threads/help-ahc-pump-issue-after-reservoir-drain-refill.1261668/post-14203243

 

[lx200inAR]

Also, no determination on if it is a shelf life issue or it was a bad batch of fluid, that appears to be untraceable since as you said, there are no markings on the bottles as to where they came from or when they were made.

 

[flintknapper]

I've talked with mt parts guys at Toyota, he knew nothing about bad fluid. He as did I look on our shelves, at bottles. No dates on them! So how can we tell a bad bottle form good?

So I just now called Lexus parts, which sees a lot more AHC systems. Parts guy said they got internal service notice (he thinks it was from shop forman, looking for me now). He recommends filtering fluid. I'd not want to even use filtered or not. I'm near end of a case I bought, without issue. But this is concerning.

Any info on fluid and why? Has Toyota or Lexus officially put anything out on this?

Agreed. Given what we know.....I would filter fluid to determine if there was a possible issue with it or not. And IF there is, return for replacement (after taking pics), but certainly don't use it.

 

[2001LC]

What a mess. We really need some office statement from Toyota. At least they need to acknowledge the issue and pull all bottles off the shelf.

From what Lexus parts guy said (filter it) implies it's jelled in the bottle. Which we can filter, to just see if bad. But I'd not use if had any jell in bottle, filtered or not.

I purchased a case 4/17/21, which I'm down to last 3 bottles. I've not had any issues with.

My fear is the stuff may jelly after put in AHC system.

 

[Jcreme]

Welp, ultimately, my pump or motor failed. I'm getting a new assembly. FML

I can offer insight into the fluid and how to avoid my fate. The fluid is easily filtered. It does not seem to gel further or out of the bottle, and personally, I am confident with it once filtered. I suspect the fluid is interacting with the plastic bottles or, more likely, the oil on the bottle from the bottle manufacturing process.

My recommendation: filter the fluid into a glass container to allow visual inspection. I found filtering with 4 layers of simple cheese cloth (from the grocery store) was 100% effective. Putting into a clear container really just offers assurance. The gel shows as white flecks in the fluid.

Here's some pics!

Here is the gel caught in the cheese cloth

I put it into this jar I had. It is 100000% worth it to go to Walmart and get some 1qt mason jars if you don't have something on hand. 1 will do. 2 is more convenient.

This was fluid that had gel in it. You can see it is now perfectly clear. I filtered again with the cheese cloth into the reservoir - but mostly because I was so damn mad. Its not really necessary.

 

[Jcreme]

Can I ask. Where did you buy the AHC?

Update: When the Lexus parts manager asked for a copy of the receipt, I realized I had actually bought the fluid from the Toyota dealer next door.

I got it at Westside Lexus Don McGill Toyota in Houston TX. I bought their whole inventory (6qt) so maybe I fixed this for everyone else.

 

[TwistedCon]

Curious. Did you buy OEM globes or go a different route? My AHC is riding rough and checked the graduation marks. Looks like only 5. Going to double check stuff when my techstream gear comes in the mail. But looking to replace.

Also order some AHC fluid last week from the dealer. So curious to see how the bottle or cans end up looking.

 

[Jcreme]

Curious. Did you buy OEM globes or go a different route? My AHC is riding rough and checked the graduation marks. Looks like only 5. Going to double check stuff when my techstream gear comes in the mail. But looking to replace.

Also order some AHC fluid last week from the dealer. So curious to see how the bottle or cans end up looking.

Got OEM from IMPEX Japan. They were about $135 each. I had about the same - 5 graduations. And a little bouncy. All other specs were ok. No idea what the results of the new globes arre yet

 

[TwistedCon]

Wow significantly cheaper than what I was finding. That's good! Once you get your issues sorted let me know how it works out.

 

[2001LC]

One thing about counting graduations H to L. Useless data, until system is properly tuned.

Whereas I've never seen 5 grads, even at over 350K miles 22 years old. I've seen plenty of 7 or 8 grads pre tune up of AHC system, go to 9, 10, 11 even 12 after a tune.

Due to this fluid issue, I'm saving my few bottles for repairs. I'm delaying all flushing, until I know WTF going on with jell in fluid. I'll just filter old fluid for now, through a transmission filter. when I need to.

 

[TwistedCon]

One thing about counting graduations H to L. Useless data, until system is properly tuned.

Whereas I've never seen 5 grads, even at over 350K miles 22 years old. I've seen plenty of 7 or 8 grads pre tune up of AHC system, go to 9, 10, 11 even 12 after a tune.

Due to this fluid issue, I'm saving my few bottles for repairs. I'm delaying all flushing, until I know WTF going on with jell in fluid. I'll just filter old fluid for now, through a transmission filter. when I need to.

When you mean tune are you referring to height sensors working properly and being at the proper pressures in N?

 

[rc50cal]

My truck is also now throwing the code 1762 abnormal pump pressure. I too used Toyota AHC fluid (bought from a Toyota dealer) from plastic bottles to flush my AHC system. Code won't clear (or at least won't stay cleared). The truck will go from high to low but the process takes a long time.

 

[MarkTR]

Well, there goes the four plastic bottles I have on the shelf. With everyone's help, I had set up the pressure and higths with the TS and was going on to perform a full flush this fall. But I got into working on other issues on the truck and never got to it. I only used a small amount topping off the system and did not see any gell coming out-but unless it makes a small splash, I do not think I would have even noticed.

I might strain all four and post back what I see.

 

[uHu]

When you mean tune are you referring to height sensors working properly and being at the proper pressures in N?

Yes. Pressures and heights at spec.