Grab a screenshot of main and motor relay descriptions/commands.
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- Thread starter
- #42
But no liquid is coming out of anything maybe just a few drops. Does this still count as “bleeding” at this point?
Yes, potentially. You're bleeding air, I think. Picture a slug of air 4' long in the lines. It's going to take some moving to get that all out.
- Thread starter
- #44
- Thread starter
- #45
So bleed accumulator, then all 4 globes, then start car try to move to N, wait a bit, turn off, repeat?
Perfect. I think motor relay is your jam here. That should forcefully run the pump... I think. I'd run that for 10 seconds, bleed, repeat, etc... Until you can get the pump to run with idling and maybe a height change command.
If the pump runs each time you start, yes. Alternatively you can force it to run with Techstream, but be mindful not to let it run too long.
- Thread starter
- #48
How do I force it to run with tech stream? As far as I can tell the active test tab does nothing
If pressing ok on that screen didn't do it, I suspect you have the option under utility tab.
- Thread starter
- #50
Gotcha I’ll try that
- Thread starter
- #51
I can sometimes get the flashing OFF but only after bleeding the accumulator the motor whine but then fails and nothing happens. I have techstream I’m now getting code c1762 abnormal oil pressure. I tried the active test from that thread by shooting ts e1 pins in DLC1 port but nothing happened.
- Thread starter
- #52
@LndXrsr @suprarx7nut ive seen people with similar problems and it ended up being the height control sensors. Could this also be it?
EDIT: Sorry, my phone went haywire and didn’t load the last dozen posts. Ignore
sensors can be trouble, but without Techstream readings from a system in N, it’s hard to figure out if one is bad. This still seems like an air/bleeding/pump issue to me
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- Thread starter
- #54
No worries, so if anything is bad it’s the pump? And only way to find out is to continually bleed it until something different happens? Or like @suprarx7nut says and manually run power to the pump and try that
I'm with @LndXrsr . Bleed problem. Could be bad pump, but far more likely bleed problem, IMO.
Another user recently faced something similar. I think they did a bleed and accidentally left the accumulator bleeder open longer than intended, sucking air back into the system. The result was a tedious bleed process that had them convinced something else was wrong. In the end it was just a big slug of air trapped in the system that took many bleed cycles to work out.
Also note that once you get the pump to run, the height accumulator can take a long while to fill. You have to let the car idle after it's done moving to whatever height you select for at least 60 seconds, probably even longer, before it fills the height accumulator. The manual says 30 seconds, I believe, but mine took much longer and had me thinking there was a problem. There wasn't - just needed to wait a little longer for the height accumulator valve to open up and fill.
As long as you can hear the pump kick on (even just momentarily), I would continue to bleed.
If you're questioning if it's doing anything, maybe time how long the pump runs so we know what's going on. If you get tired of the process, try the Techstream utility to force it to run.
Another user recently faced something similar. I think they did a bleed and accidentally left the accumulator bleeder open longer than intended, sucking air back into the system. The result was a tedious bleed process that had them convinced something else was wrong. In the end it was just a big slug of air trapped in the system that took many bleed cycles to work out.
Also note that once you get the pump to run, the height accumulator can take a long while to fill. You have to let the car idle after it's done moving to whatever height you select for at least 60 seconds, probably even longer, before it fills the height accumulator. The manual says 30 seconds, I believe, but mine took much longer and had me thinking there was a problem. There wasn't - just needed to wait a little longer for the height accumulator valve to open up and fill.
As long as you can hear the pump kick on (even just momentarily), I would continue to bleed.
If you're questioning if it's doing anything, maybe time how long the pump runs so we know what's going on. If you get tired of the process, try the Techstream utility to force it to run.
- Thread starter
- #56
We finally figured it out. Big shoutout to @ktmracer01 who came over several times to help diagnose it with me. At first after reading many threads on similar sounding issues, we figured that there was just a ton of air in the system, and it just needed to be bled out no matter how long it took. So we did that following Paddo's method for probably a total of 5-6 hours or so and got the system to finally come out of limp mode. Pressure starting going back into the globes, but trying to cycle it would just throw it back in L and it would start flashing OFF again. During this time while trying to bleed all the air out of the lines, the pump was working, but it was whining and it seemed to be heating up very fast. We even tried bleeding the attenuator that is connected by hardline to the pump after reading that solved someone's problem, but to no avail. Finally we decided it must be the pump, after so many hours of bleeding fluid with air bubbles in it with very little change. Installed a new pump and it has been functioning perfect ever since. I only encountered this problem after installing brand new OEM globes. This led us to believe that the bad pump probably had a bad o ring or gasket somewhere but was still able to function because of sediment buildup from the old fluid. But after flushing and bleeding the system so many times with fresh fluid the sediment became dislodged and air started to be sucked into the system every time it was cycled. (@ktmracer01 feel free to explain this better.) Now pressures are just about in spec as well. The front is a touch high at 7.1 (ARB front bumper), but the torsion bars are all the way cranked so may need beefier torsion bars eventually. The rear is fairly low at about 4.3 but I have KTRS King springs in the rear with 30mm spacers from Ironman that @ktmracer01 also graciously helped me install as well. Even with a RTT, Drawers, and full roof rack it still low. Should be about perfect after a rear bumper though. Thanks again everyone! Hope this can help someone else out!
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ktmracer01
SILVER Star
@Eltestro No problem at all. That's what the Toyota LC / LX family is all about.
A few things to note before we started troubleshooting it:
1. Torsion bars had been tightened to almost max to help take load off of the suspension. (rooftop tent, arb fridge, arb drawer, full pull out camp kitchen, arb front bumper, and winch)
2. The first fluid bleed was done because there was suspected air in the system
3. All four (4) globes were replaced after guidance from Mud and other technical sources as well as installed King springs
4. After all 4 globes were replaced, the shop he took it to mentioned they were still having trouble getting all of the air out of the system
5. System would get upset as soon as it got warm. Usually after the first cycle of the suspension.
6. You couldn't actually get an accurate pressure reading with techstream because the system wouldn't come out of "L" consistently.
What we did:
1. As he mentioned above, after trying to bleed any air out of the system (including a vacuum bleed at each globe and the accumulator). Minimal improvement
2. Installed Rear coil spring spacers to help pre-load the rear springs, this was when we found the rear height sensor was not re-installed and tightened properly after the rear springs were installed.
3. Tried to bleed and cycle the suspension a few more times. We still continued to get micro-bubbles, and the fluid temp was getting really high. I don't remember the exact temperature it was getting up to, but it was too hot.
What we concluded:
Between the unusual amount of noise the pump was making after it got warm, and the fluid temp, I suspected we were getting air entrainment at the pump.
What fixed it:
After a 30-45 min pump swap (including cycling the pump, bleeding air out of the system, and checking for any leaks)...cycled the suspension several times and it worked flawlessly.
Pressures are still a little high on the front, but in general, seems to handle all of the extra weight he's added very well.
What's next:
1. We'll see if we can loosen the torsion bars a little and get the front pressures closer to where they need to be. I suggested heavier TB's since I'm already running them on my LX with AHC. I don't have nearly as much weight on the front as he does.
2. Pull apart the old pump to see what could have caused any air to get sucked in when the pump was running, re-build it, and see if it does the same thing.
A few things to note before we started troubleshooting it:
1. Torsion bars had been tightened to almost max to help take load off of the suspension. (rooftop tent, arb fridge, arb drawer, full pull out camp kitchen, arb front bumper, and winch)
2. The first fluid bleed was done because there was suspected air in the system
3. All four (4) globes were replaced after guidance from Mud and other technical sources as well as installed King springs
4. After all 4 globes were replaced, the shop he took it to mentioned they were still having trouble getting all of the air out of the system
5. System would get upset as soon as it got warm. Usually after the first cycle of the suspension.
6. You couldn't actually get an accurate pressure reading with techstream because the system wouldn't come out of "L" consistently.
What we did:
1. As he mentioned above, after trying to bleed any air out of the system (including a vacuum bleed at each globe and the accumulator). Minimal improvement
2. Installed Rear coil spring spacers to help pre-load the rear springs, this was when we found the rear height sensor was not re-installed and tightened properly after the rear springs were installed.
3. Tried to bleed and cycle the suspension a few more times. We still continued to get micro-bubbles, and the fluid temp was getting really high. I don't remember the exact temperature it was getting up to, but it was too hot.
What we concluded:
Between the unusual amount of noise the pump was making after it got warm, and the fluid temp, I suspected we were getting air entrainment at the pump.
What fixed it:
After a 30-45 min pump swap (including cycling the pump, bleeding air out of the system, and checking for any leaks)...cycled the suspension several times and it worked flawlessly.
Pressures are still a little high on the front, but in general, seems to handle all of the extra weight he's added very well.
What's next:
1. We'll see if we can loosen the torsion bars a little and get the front pressures closer to where they need to be. I suggested heavier TB's since I'm already running them on my LX with AHC. I don't have nearly as much weight on the front as he does.
2. Pull apart the old pump to see what could have caused any air to get sucked in when the pump was running, re-build it, and see if it does the same thing.
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Awesome run through! Thank you for posting this.
I just disassembled an old AHC pump. They're super simple. A few O ring seals and that's really it. It would be awesome to learn if the old pump here is corrected with new O-rings. That pump has almost nothing to go wrong aside from O-rings or really unusual wear on the gears. If it's pulling in air, I think it would have to be at the o-ring seals or the motor shaft seal. All pretty cheap parts to R&R.
ktmracer01
SILVER Star
@suprarx7nut I'm really anxious to get it pulled apart. I already ordered parts to rebuild. Looking at the FSM and the photos you posted, there's not much to these pumps at all.
ktmracer01
SILVER Star
@suprarx7nut I had a chance to pull the pump apart earlier this week and was surprised by the following:
1. Very simple design and easy to disassemble. 10mm socket and 1 allen wrench for all hardware to pull it apart.
2. The amount of sludge and the gelatin-like gunk that was in it after most of the fluid had been drained and the number of times the system was flushed before it was removed. (at least a dozen times. @Eltestro can correct me if I'm wrong)
3. The internal pump gaskets are not easy to source <- this could just me being lazy.
I haven't been able to exactly identify the cause of the pump failure, but based on the gelatin nature of the sludge that was in there, I fully expect that to have played a major role in the pump not cycling fluid properly. I did a visual inspection of all the gaskets and I couldn't find any tears or obvious defects that would cause it to suck air. And, the pump wasn't leaking any fluid before pulling it from the truck.
After cleaning it up a little bit, there was evidence of wear on the motor coupler and also some light scratches on the inside of the pump cover. Some type of debris went through it, but I can't find anything that would have caused the scratches yet.
The gaskets that I ordered just arrived, but as I pulled it apart, I realized I didn't have a "full" rebuild kit ordered. As I pulled things apart more, I realized the internal pump assembly has five (5) additional o-rings/gaskets; one that looks a little like a house, and two small round o-rings, and also two (2) metallic gaskets that I haven't located on a parts diagram.
I was able to source the internal pump as a complete unit online and should arrive sometime in mid-August from partsouq. At this point, probably in this pump for around $200.00USD with all of the gaskets and internal pump.
I'm starting to suspect that this may be a leading factor to most people having issues with their AHC. If the system hasn't been flushed regularly, it would be very easy to have deposits build up in the pump. Also, the AHC fluid is hygroscopic (absorbs moisture), so if the vehicle sits for a long time or if it isn't flushed regularly, it will eventually absorb some moisture. Depending on the climate, that could be a little or a lot. Just my 2cents.
Seems like this would be a good place to start for people that are having AHC issues before committing to new globes, etc. Obviously depending on DTC's that present themselves.
1. Very simple design and easy to disassemble. 10mm socket and 1 allen wrench for all hardware to pull it apart.
2. The amount of sludge and the gelatin-like gunk that was in it after most of the fluid had been drained and the number of times the system was flushed before it was removed. (at least a dozen times. @Eltestro can correct me if I'm wrong)
3. The internal pump gaskets are not easy to source <- this could just me being lazy.
I haven't been able to exactly identify the cause of the pump failure, but based on the gelatin nature of the sludge that was in there, I fully expect that to have played a major role in the pump not cycling fluid properly. I did a visual inspection of all the gaskets and I couldn't find any tears or obvious defects that would cause it to suck air. And, the pump wasn't leaking any fluid before pulling it from the truck.
After cleaning it up a little bit, there was evidence of wear on the motor coupler and also some light scratches on the inside of the pump cover. Some type of debris went through it, but I can't find anything that would have caused the scratches yet.
The gaskets that I ordered just arrived, but as I pulled it apart, I realized I didn't have a "full" rebuild kit ordered. As I pulled things apart more, I realized the internal pump assembly has five (5) additional o-rings/gaskets; one that looks a little like a house, and two small round o-rings, and also two (2) metallic gaskets that I haven't located on a parts diagram.
I was able to source the internal pump as a complete unit online and should arrive sometime in mid-August from partsouq. At this point, probably in this pump for around $200.00USD with all of the gaskets and internal pump.
I'm starting to suspect that this may be a leading factor to most people having issues with their AHC. If the system hasn't been flushed regularly, it would be very easy to have deposits build up in the pump. Also, the AHC fluid is hygroscopic (absorbs moisture), so if the vehicle sits for a long time or if it isn't flushed regularly, it will eventually absorb some moisture. Depending on the climate, that could be a little or a lot. Just my 2cents.
Seems like this would be a good place to start for people that are having AHC issues before committing to new globes, etc. Obviously depending on DTC's that present themselves.
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