Recently purchased and LR3 07 107k miles. And a gap iid tool.

the truck is stuck on the bump stomps and I’m getting ready to jump into it tomorrow.

My main fault is C1A20-64 (AF) Pressure increases too slow when filling reservoir - Algorithm based failure - signal plausibility failure


today while checking gallery pressure and all other items in live values. Nothing was seeming incorrect

But I did notice that the gallery pressure shows about 99 then when the compressor kicks in. Maybe goes to 110 max. Before faulting out.


is 99 a base number? ( should this be 0 if sitting like this for months)

ddoes this lead to think there is pressure in the system but it’s failing to add more??

or a faulty center block / pressure sensor.

AMK style compressor. Previous owner said that it is only a couple of years oLD. And the car came with another older amk compressor as well

going to do soap water test tomorrow and go from there. Just curious if anyone has thoughts on this pressure

 

Weird, mine shows PSI next to the value when I bring it up. You only get a number? I would assume then it would be PSI and 110 is way too low. That is barely enough to lift the truck, heck it may not be. I think 120-150 psi is needed. Max gallery pressure when filling reservoir should be about 250psi but varies on software version. So yeah, you have a leak or faulty compressor.

 

in live values? Maybe I’m looking at the wrong place.

 

Yes.

 

Oh I haven’t seen that screen where do you get to that??

 

When I go to live values/complete list/air suspension and pick the ones I want and press trigger

 

ah yea. I was just watching the numbers in complete list while they’re selected. Just didn’t go to next screen lol.

 

So now that that is figured out. The LR3 will first try to raise the rear end followed quickly by the front. Unless you have an issue. The reservoir is the last thing to ever fill and the pressure reading is not the reservoir, only the gallery. Which will leak down and that is normal. It is pretty much just the pipe work, so not much volume.

 

I thought the reservoir filled first? Being that this has been on the bump stops for awhile it’s 100% empty all around.

if the reservoir fills last. Them I’m guessing either dryer, leak at the center valve block or stuck / broken solenoid at that block. Or possibly exhaust valve stuck open.

I was thinking maybe compressor tank but if that comes last in theory the truck shoold
move up some before that leak stops it?

 

Nope. Last. The reservoir only serves one purpose, to make a height change upwards faster.

Broken solenoid would not do it.

Basically the system starts the compressor and NOTHING opens for about one second. That is so the gallery pressure can get up to at least 150psi before a solenoid to anything is opened. Why? If a valve blocked opened right away and the gallery pressure was zero the strut could drop a small amount because air would go out, not in. So for a change up in height the compressor starts and reaches min psi, reservoir will open to assist, then one second later usually a rear valve block will open followed quickly by the front. If the reservoir was empty, you may often get "vehicle raising slowly" on the dash.