8 months ago truck burst the drivers rear feed pipe from control valve to sphere. I ended up replacing all the feed pipes from each sphere to control valve and replaced fluid with proper toyota stuff. Truck eventually levelled up with some playing about with diagnostic active tests of actuating front and rear levelling solenoids. Drove it for 5 miles and it suddenly dropped both drivers front and rear corners. Put it back on ramp and the feed pipe from drivers rear sphere to shock was weeping so I assumed loss in pressure caused the drop. Toyota wanted £400 plus vodka and tonic for pipe so managed to source from UAE for £130 plus shipping  Pipe arrived after a long wait with shipping restrictions, got it fitted and now I have a new issue. As soon as truck levels up on N height it holds pressure for 1-2 secs then drops on drivers side. Checked height sensors all seem fine. Have tried bleeding/driving and all sorts but I have a 10cm difference between front heights and led is holding at N. I’m having a wild guess but it seems to me like the control valve may be faulty it is showing no DTC codes. Or is possible I have mixed up the control valve feed pipes when replacing as the truck is raising left side/right side not front/rear? |
AHC issue (1 Viewer)
- Thread starter L18 CGL
- Start date
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ramangain
Clarksonian disciple
What are your sensor heights and pressure readings after a L to N cycle?
- Thread starter
- #3
It won’t hold a L to N cycle as soon as LED stays solid on N it collapses on drivers front and rear. height sensor values are constantly changing throughout actuation
ramangain
Clarksonian disciple
Do you own a diagnostic tool like Techstream to watch height sensor and pressure sensor values during and upon completion of a L to N cycle?
If so, please post screenshots of data.
If so, please post screenshots of data.
How is that possible? I thought these pipes are solid & can only go way onto the valve?
@L18 CGL: It is a big job replacing all those pipes, glad it worked out for you in the end!!
I have a simple problem -- I would like to check the resistances of the solenoid valves in the Control Panel Assembly on my vehicle. Maybe it is just old or inept fingers but I cannot get the electrical connector to release -- what I should be doing to get the lock to release so as to withdraw the harness connector from the Control Valve Assembly?? Ditto the connector on the Height Control Accumulator??
- Thread starter
- #9
Its a lot easier with copper than the steel toyota pipes more flex lol I would say just dirt is making the connector stiff you can see the release clip. Trying pushing in on the plug at same time as pressing release clip they can be stiff
Ah okay. I thought it was with the factory pipes
ramangain
Clarksonian disciple
Indro, for starters try a couple cans of compressed air, and maybe some baby oil (?), to loosen up and remove that crud. A pick tool would surely help too
