AHC system help!

[vsatking]

That is on my read list. I am on this one now.

09 LX570 - AHC Failure

Greetings folks. I live in Toronto, Canada and I drive a 09 LX570 with 236,000 KM on the clock and few days ago the AHC started giving up on me. It was a rainy day and the truck was driving fine, up until I added one luggage (probably 10-15kg) into the trunk and drove off. 5km later the...

forum.ih8mud.com

 

[Sandroad]

I’m ignorant about AHC, but I know there is a sticky thread on it. Also, I remember an issue in the past with contaminated fluid being sold at dealers. Any chance of previous work on yours being affected?

LX570 AHC “Basics” - Added as sticky thread for AHC Issues

Point of this thread is to serve as a repository for 200-series AHC info, including LX570 and LC equipped with AHC (in select global markets). Let’s begin with a theory. The 200-series LC (without AHC) and the LX570 (or LC with AHC) are like New York & LA. LC “purists” are like New Yorkers...

forum.ih8mud.com

 

[vsatking]

I’m ignorant about AHC, but I know there is a sticky thread on it. Also, I remember an issue in the past with contaminated fluid being sold at dealers. Any chance of previous work on yours being affected?

LX570 AHC “Basics” - Added as sticky thread for AHC Issues

Point of this thread is to serve as a repository for 200-series AHC info, including LX570 and LC equipped with AHC (in select global markets). Let’s begin with a theory. The 200-series LC (without AHC) and the LX570 (or LC with AHC) are like New York & LA. LC “purists” are like New Yorkers...

forum.ih8mud.com

That is a real possibility. Hard to say. That could have burnt out my pump if that is the real issue. I will read through the sticky next. Thanks for the help!

I am debating on ordering a new pump and get it shipping here. I can do a full system flush as I now have two jugs of fluid and see if that works. I might just do that first then see how the pump reacts. Because of the cold issue I think there still might be some issue with water in the lines somehow. I will start with the easiest then go from there. I am also going to do a good personal inspection. The fluid had to leak out somewhere!

 

[lx200inAR]

It's not impossible that the pump is bad, but if it works when it's warm outside, hard to imagine. Either way, here it is on eBay for $1k for a new one from UAE.

GENUINE Toyota LAND CRUISER LEXUS LX570 PUMP MOTOR HEIGHT CONTROL 48910-60032 | eBay

Find many great new & used options and get the best deals for GENUINE Toyota LAND CRUISER LEXUS LX570 PUMP MOTOR HEIGHT CONTROL 48910-60032 at the best online prices at eBay! Free shipping for many products!

www.ebay.com

Not sure how much of that $4400 was the inflated US part price or just the mechanic giving you an F-U price so you will take it somewhere else.

Is there any explanation for where the fluid went? I'll start by saying, it can be very difficult to see fluid in the reservoir, Its generally easier to see from under the truck looking from where the spare tire is.

edit: I'd want to do some investigation before i assumed my pump was bad. It's possible it got run dry and burned up, but there are definitely fail-safes to keep that from happening (like your low pressure DTC).

 

[vsatking]

I just picked up the LX. I felt the dealer was being up front and honest with how they approached the error. They said the factory pump is near $3000 with a little over $1000 in labor. Looks like online lexus pumps are about $2300 after a $700 online discount.

Good aftermarket pumps are $1000. Not bad!



I also did another very good system flush. 2 drops per 5 bleed points. Tmis makes a total of 4 drops per 5 bleed points. Out of the 20 or so up/dn in the past week in my heated garage there have been no issues. Only issue is while parking in the cold.







I left the LX outside tonight to see how the flushes worked.







This is strange!

 

[lx200inAR]

I just picked up the LX. I felt the dealer was being up front and honest with how they approached the error. They said the factory pump is near $3000 with a little over $1000 in labor. Looks like online lexus pumps are about $2300 after a $700 online discount.

Good aftermarket pumps are $1000. Not bad!



I also did another very good system flush. 2 drops per 5 bleed points. Tmis makes a total of 4 drops per 5 bleed points. Out of the 20 or so up/dn in the past week in my heated garage there have been no issues. Only issue is while parking in the cold.







I left the LX outside tonight to see how the flushes worked.







This is strange!

I wouldn’t guess that part is aftermarket. Lots of OEM parts are considerably cheaper in the Middle East than in USA. They sell a lot more 200s there than here.

 

[vsatking]

The Check AHC light came on again with front end droop. It is 25 deg outside and AHC fluid is full to the correct level. I drove it for a few miles and stopped. When i got back in and started up the AHC sys acted normal. I am going to order another pump online and get it shipping to my house. It does not seem like pump as it works normally after driving it a bit. Hate to through a $1000 at this without knowing.

 

[CanadianRockyCruiser]

I'd clean up all the electrical connections, if I were you. If the pump is working sometimes but not others, it could be a pump on the way out, but it could also be a bad electrical connection. Worth digging into and cleaning up all the pump electricial connections, however, that wouldn't explain the missing fluid...if there is no leak, then it's very likely that you had air in your system previously. If so, I'd throw more bleeds and AHC fluid at this before a new pump (maybe 2 full cans/5 litres)...just my two cents. It's also possible to clean out the filter in these pumps, which can occasionally be clogged.

 

[eatSleepWoof]

I'd clean up all the electrical connections, if I were you. If the pump is working sometimes but not others, it could be a pump on the way out, but it could also be a bad electrical connection.

This train of thought reminded of me of my first car and a problematic starter relay that would only activate (and let the car start) when it was cold. As it warmed up from engine heat, the contacts inside got a hair bit closer and the relay wouldn't work until they cooled down again. I wonder if something similar could be happening within the AHC system, but with some components contracting together from the cold temperatures? Guessing blind here...

 

[vsatking]

I found some great information on YouTube on how to replace the AHC pump. Total time for the actual pump replacement for the video was 25 min. With fluid drain, fill and bleeding I should be able to do it in an hour. I also found the FSB to do a AHC system test on toyota nation. With these two sources i have a real good idea of how to diagnose what is happening before buying a new pump.

This morning i pulled the plastic off to do a battery test of the pump. I found something suprizing and a little expected.

Keep in mind the my LX Lexus service history states the AHC pump was replaced on 8/20 at 103k mi. It now has 132k.

When looking at all the hardware and casing/shell of the pump it is really clear the pump is not 2 years old. The dealer never replaced the pump.

I also found a minor leak coming from the low fluid sensor where it unters the reservoir. That explains where the fluid leaked out.

Here are the photos. What do you think? Has this been replaced in the last 2 years? I think no way.

 

[vsatking]

I am debating how much time and mental effort I want to spend reaching out to Lexus to make a case. For $1300 and 2 hours I can replace the pump and blead the system. Like most of us. 1300 is less of the point as a problem with the records and a dealer charging the PO for work not done!

 

[vsatking]

The Check AHC system light did come on this morning as I left the LX outside in 19 deg weather. By the time I set everything up to do a direct battery test of the pump in my heated garage the pump kicked on just fine. I am on a business trip for a week. When I get back ill set everything up and do the test outside when it is cold now that I know how to do it all.

 

[vsatking]

If the pump tests good I am going to use this process to diagnose.

 

[grinchy]

Glad you found the leak. I’d use the old pump.

 

[LX Cruiser]

If the pump tests good I am going to use this process to diagnose.

Any updates on this issue? I‘d be so mad if the dealer didn’t swap the part I paid for. If I ever pay a dealer to replace a specific part, I’m going to scratch a small X into the side of it in an inconspicuous place and check it afterward.

 

[Nothinghead]

Any updates on this issue? I‘d be so mad if the dealer didn’t swap the part I paid for. If I ever pay a dealer to replace a specific part, I’m going to scratch a small X into the side of it in an inconspicuous place and check it afterward.

I always have them give me the old parts although your mark sounds more foolproof.