L322 Another L322 suspension issue!

Hi all, I'm new on here and I'm new to Land Rover ownership. Little did I know that buying the car would get me up to my eyeballs in the full time hobby of guessing "What the f**ks wrong with it now?!"!
Around eight months ago I purchased a very clean 06 supercharged. It's been bloody great with the exception of a few little niggles. A bit of pokin' and a proddin' and I've been able to suss most issues out. However, the other day I installed a brand new battery. To do so I lowered the car to "access mode" and since then have been unable to raise the thing back up to normal height. I should mention that beforehand I had an intermittent fault where after starting, the display would say "Suspension inactive, normal height only". I could immediately stop the car and restart and the fault wold be gone, everything would work and the lights around the control knob on the dash would remain illuminated as normal.
After replacing the battery I just can't get it to work. Each time I start the car, the compressor runs for about ten seconds then the lights go off on the height control knob and the display just says "Suspension Fault". With my head in the boot I can hear a hissing when the pump stops, it's coming from the pump but dies off within a second or two. Is this just a relief valve or something?
I've also seen the message "Vehicle lifting slowly". Could this be due to worn seals in the pump? I.e. If the seals just eventually went and the pump isn't making high enough pressure, would the car run the pump for say ten seconds and time out if the pressure in the system doesn't rise quickly enough? Any help very much appreciated!!
I have a cheap OBD reader but it tells me nothing about suspension. I wouldn't begrudge paying for a good one but not sure what to go for. Any recommendations?
Thanks

Full left lock then full right lock may just clear the fault.
The original problem was most likely due to the battery being poor, these cars really need plenty of battery power.

Datatek said:

Full left lock then full right lock may just clear the fault.
The original problem was most likely due to the battery being poor, these cars really need plenty of battery power.

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Yup, I did the lock to lock thing but nothing, no change. Even did the whole ECU reset thing by dissing the battery and joining the leads but alas, no change.

Mortlach said:

Yup, I did the lock to lock thing but nothing, no change. Even did the whole ECU reset thing by dissing the battery and joining the leads but alas, no change.

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Time to buy diagnostics then, have a look at www.Blackbox-solutions.com if they cover your car they are the best. NO affiliation.

One of the family P38's threw a strop with the valve block and sat on the bump stops for a week. after a valve block rebuild it wouldn't rise on the front. compressor output was fair.

Turned it off shoved a trolley jack under each side and jacked it to about the right level. turned it on let the pump run for a couple of minutes removed the jacks. it's been fine since. See if that works ?

Probably needs heights recalibrated with the software. Lost it's settings with no battery

RangeRoller dt said:

Probably needs heights recalibrated with the software. Lost it's settings with no battery

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Had the battery off my l322 couple of times just had to do the lock to lock thing after reconnecting thats all, something else amiss with it me thinks needs plugging in to find out what.

How long did he wait before disconnecting the battery?

RangeRoller dt said:

Probably needs heights recalibrated with the software. Lost it's settings with no battery

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Removing the battery does not cause loss of height settings.

myfirstl322 said:

How long did he wait before disconnecting the battery?

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Pretty sure that wouldn't have any issue to do with the ELS, however more commonly it does and can blow the entertainment ECU's, Satnav etc instead.

So I followed the factory procedure to the letter when I replaced the battery. Current status is, I start the car with doors closed, initially the middle and lower light to the right of the height control knob illuminate and the compressor runs for roughly 10-12 seconds at which point it stops, lights on height control go off and I get a chime with "Suspension Fault" on the dash. There may indeed be some calibration required as when I look at the 4x4 info screen, it says "Standard height" even though the display clearly shows the car is sitting on its arse.

Mortlach said:

So I followed the factory procedure to the letter when I replaced the battery. Current status is, I start the car with doors closed, initially the middle and lower light to the right of the height control knob illuminate and the compressor runs for roughly 10-12 seconds at which point it stops, lights on height control go off and I get a chime with "Suspension Fault" on the dash. There may indeed be some calibration required as when I look at the 4x4 info screen, it says "Standard height" even though the display clearly shows the car is sitting on its arse.

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It needs diagnostics.

So a wee update guys. I was suspicious that I was hearing the compressor exhausting air into the cabin very shortly after it starts running and when the compressor stops cycling, the exhausting air would just peter off rather than shutting off. My experience in engineering told me that this being the correct mode of operation was very unlikely. In my head it made sense that either a preloaded pressure relief valve was faulty (maybe a weak spring) or a valve which is usually actuated on or off by the system was stuck open, damaged etc,etc. I did what I have seen many people tell others not to. I bought a pretty comprehensive rebuild kit from ebay, including a delivery valve kit (little plunger, preload spring and o-ring). I rebuilt the compressor, (including dryer dessicant, filters, piston ring, seals, o-rings etc) which was a doddle and only took about 40 minutes and reinstalled. I started the car and crossed my fingers. The compressor ran for what felt like ages but sure enough, up went the car! Still no controls though. The ride height selector lights remained off. After checking, I found it had brought the car up to standard height. I took it for a good run and the next time I started it everything worked. Suspension is now fully working, including controls and raises and lowers correctly. I parked it a couple of days ago and have been taking regular measurements of the ride height on all four corners and after the initial levelling period, nothing has shifted so I know I don't have any leaks. Also, since rebuilding the pump, it seems to run a lot less when I'm out in the car. I'm now left with two issues, a rainwater leak into the spare wheel well and a brand new issue, my MOST network is broken!

Glad you got it sorted, glad I have no EAS too