You are on the right track. After changing my globes I got an error on first cycle. Restarted and tried again, truck went up slowly but didn’t fully indicate high. Took a couple of cycles after globe install and bleed procedure.
HELP Needed AHC 2010 LX570 (1 Viewer)
- Thread starter Solboricua
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You are on the right track. After changing my globes I got an error on first cycle. Restarted and tried again, truck went up slowly but didn’t fully indicate high. Took a couple of cycles after globe install and bleed procedure.
- Thread starter
- #22
Good info. I finally got to the Suspension Control Pump Accumulator nipple and bleed it. Barely any fluid came out. I am now charging the battery to full power before I try again. I will go ahead and once connected the battery I will see what if any code I get. Also to note that when I bleed the other 4 accumulators today a significant amount of fluid came out, mainly in the drivers side and barely any fluid on the passenger side.
Quick question. In techstream how do I raise the vehicle? Raise with accumulator or the option or cycle up and down? Lastly when bleeding I am thinking of doing the drivers front and then the passengers front before I start the vehicle back up. Is it better to bleed one side then turn on the car and do that cycle a few times till there is no more air in the system or should I do both fronts? Lastly in techstream how can I force the pump to work? (AHC pump check and force the pump to run).
So if you didn't get any fluid out when you bled system immediately after you changed the globes and you did get fluid out today, then I suspect you just aren't letting it pump enough to replace all the fluid you have removed from the system.
I would hook up your Techstream and watch the "oil pressure sensor" field. Monitor that when you push the lift button. You should only be trying to lift with engine running and all doors closed. You know it's trying to lift if the arrow is flashing up on the dashboard. When monitoring the "oil pressure sensor" field you will only see the number change while the pump is working (before and after the pump runs it will always show .16 MPa). Let the pump run the full 30s until it stops (arrow stops blinking and probably hear pump stop). Hopefully while the pump was running you saw the reading go up a little, but probably not high enough (looking for around 8 MPa going to N at peak when at proper pressure). My guess it that the reading will go up, but less than 8MPa. Then you will get the check AHC light and a code for pump pressure. All you need to do is restart the truck and then hit the lift button again before the check AHC light comes back on (you'll have a few seconds after startup before it comes on). Watch Techstream again and see if that value increases again. Hopefully this time to a higher number. If it goes higher than the first time, then you are on the right track. I'd keep repeating these steps until the truck starts lifting. I would not bleed again until you have gotten the truck to lift. If it doesn't lift there really isn't anything to bleed.
Once you get the truck back up to N, then i'd do a bleed procedure.
Before doing all this, make sure you don't/haven't let the AHC fluid reservoir run dry. I would be tracking the difference between how much I've put in and how much I've taken out.
Also, a side note the FSM says that C1783 is the pressure error, not anything to do with a specific wheel sensor.
I would hook up your Techstream and watch the "oil pressure sensor" field. Monitor that when you push the lift button. You should only be trying to lift with engine running and all doors closed. You know it's trying to lift if the arrow is flashing up on the dashboard. When monitoring the "oil pressure sensor" field you will only see the number change while the pump is working (before and after the pump runs it will always show .16 MPa). Let the pump run the full 30s until it stops (arrow stops blinking and probably hear pump stop). Hopefully while the pump was running you saw the reading go up a little, but probably not high enough (looking for around 8 MPa going to N at peak when at proper pressure). My guess it that the reading will go up, but less than 8MPa. Then you will get the check AHC light and a code for pump pressure. All you need to do is restart the truck and then hit the lift button again before the check AHC light comes back on (you'll have a few seconds after startup before it comes on). Watch Techstream again and see if that value increases again. Hopefully this time to a higher number. If it goes higher than the first time, then you are on the right track. I'd keep repeating these steps until the truck starts lifting. I would not bleed again until you have gotten the truck to lift. If it doesn't lift there really isn't anything to bleed.
Once you get the truck back up to N, then i'd do a bleed procedure.
Before doing all this, make sure you don't/haven't let the AHC fluid reservoir run dry. I would be tracking the difference between how much I've put in and how much I've taken out.
Also, a side note the FSM says that C1783 is the pressure error, not anything to do with a specific wheel sensor.
| DTC | Code Detection Condition | Trouble Area |
| C1763 Abnormal Pump Motor Oil Pressure | While the motor relay is in operation, the condition that the fluid pressure is 0.6 MPa (6.1 kgf/cm2, 87 psi) or less continues for 0.6 seconds. | Harness or connector Suspension control relay Height control pump and motor Suspension control ECU |
- Thread starter
- #24
Ok so did as you mentioned and this is what I got.
1) When I started the car I flipped the switch to raise the vehicle and the oil pressure reading only went up to about 1.5, as I kept doing this the pump would cycle and the readings would fluctuated from 0.5 to 3.0 at the highest level. I think I will continue to bleed the system. If this does not make any difference I think I will need to buy a new pump/motor.
- Thread starter
- #25
well nothing else new. Any good source for the pump and motor?
I'm no AHC expert here, frankly the system terrifies me (and I need to do my globes)... but check out this thread...
Based on what I've read, and some of the posts where people have had issues post bleed, I might take the pump apart and see if the screens are clogged with fine debris before replacing it...
forum.ih8mud.com
Based on what I've read, and some of the posts where people have had issues post bleed, I might take the pump apart and see if the screens are clogged with fine debris before replacing it...
New Member Intro - 2013 LX570 - Also an AHC Alert!!!
I just wanted to drop in and introduce myself, as I recently purchased a 90k mile 2013 LX570 in Starfire Pearl White, and have been constantly browsing over the wealth of information that this forum has to offer for a few months now in preparation of that purchase. I'm new to this forum, but not...
forum.ih8mud.com
nwfl4runner
GOLD Star
what procedure did you go through to test?
I'm no AHC expert here, frankly the system terrifies me (and I need to do my globes)... but check out this thread...
Based on what I've read, and some of the posts where people have had issues post bleed, I might take the pump apart and see if the screens are clogged with fine debris before replacing it...
New Member Intro - 2013 LX570 - Also an AHC Alert!!!
I just wanted to drop in and introduce myself, as I recently purchased a 90k mile 2013 LX570 in Starfire Pearl White, and have been constantly browsing over the wealth of information that this forum has to offer for a few months now in preparation of that purchase. I'm new to this forum, but not...
Take a deep breath, and don't be terrified. Most of the gotchas are known at this point.
Yeah, I’m just not the most skilled- Bleeding is one thing but removing the pump I feel is above my pay grade.
Check out this thread before you get too deep into ordering parts.
forum.ih8mud.com
AHC Pump Fun - Disassembly and Clean - Verbose Edition
Story Time: 2013 LX570 111,000mi - California truck with no rust. I posted in the SQOD thread that on a flush from Normal height there was a suction on the reservoir and that breaking the suction kept things running well when repressurizing the system. The pump took a very long time to regain...
forum.ih8mud.com
nwfl4runner
GOLD Star
Ok, when you start up the truck you get the pump low pressure DTC? If you have techstream connected, clear the DTC then go to the AHC Test utility in techstream, and test raising the front driver side (again, with DTC cleared). Does THAT do anything?
- Thread starter
- #32
I will def do this before I order anything. Do I need to have the car off the ground when I remove the pump?Check out this thread before you get too deep into ordering parts.
AHC Pump Fun - Disassembly and Clean - Verbose Edition
Story Time: 2013 LX570 111,000mi - California truck with no rust. I posted in the SQOD thread that on a flush from Normal height there was a suction on the reservoir and that breaking the suction kept things running well when repressurizing the system. The pump took a very long time to regain...
- Thread starter
- #33
Turned the car on and quickly pressed the up bottom to raise the car, and as it was on I had tech stream on monitoring the oil pressure readings and recording it. As the error message came up I turned the car off and turned it on again and did this to check the pressure readings.
- Thread starter
- #34
I tried to clear the code and as soon as it cleared the system would do the “checking” and quickly thereafter went into “check 4-wheel AHS system”. Hence I could never get the error erased while the car was running.
I believe that the FSM for pump removal is in that thread. I would follow that if your plan is to remove the pump.
nwfl4runner
GOLD Star
ok when you are in techstream, if you clear the DTC with car running does error immediately return?
- Thread starter
- #37
Yes it returns right away.
Have you tried removing the fuse in the engine compartment. When one of my lines failed I removed the fuse in the engine compartment (because I had to move the truck several times) to prevent the pump from working. When I finished replacing the line, I replaced the fuse and didn't even have to use techstream to clear the code.
- Thread starter
- #39
Well some updates:
Took the AHC pump and disassembled it. It had a lot of particles in the tank and the filters were filthy. I second the need to not remove the filter in the inlet hose when adding AHC fluid. I cleaned the entire motor and put it back together, installed it and now it does not even prime. Code still comes up.
I went ahead and ordered a new pump from partsouq...hopefully quick shipping. Too many problems at hand and too many cooks in the kitchen prior to me. Also all 4 shocks were replaced, the 4 globes and now the pump. I only pray that I never have to service the suspension.
Will keep you guys in the loop. Thanks so much for all your help.
Took the AHC pump and disassembled it. It had a lot of particles in the tank and the filters were filthy. I second the need to not remove the filter in the inlet hose when adding AHC fluid. I cleaned the entire motor and put it back together, installed it and now it does not even prime. Code still comes up.
I went ahead and ordered a new pump from partsouq...hopefully quick shipping. Too many problems at hand and too many cooks in the kitchen prior to me. Also all 4 shocks were replaced, the 4 globes and now the pump. I only pray that I never have to service the suspension.
Will keep you guys in the loop. Thanks so much for all your help.
TheGrrrrr
GOLD Star
Take some satisfaction in knowing that your efforts and documentation here will help many others. It’s certainly appreciated even by folks like me who don’t have AHC, but have friends who do.
