Started car, suspension loan.

Checked power to compressor, no power. That is a good thing I guess.

Connected Nanocom went into. I think settings and manually switched on pump. Pump immediately started, raised the back and then the front.

Experimented by going through high to low setting twice and all working. Switched off and left.

That was last night so will have another check later today and try and find some earths and check the multi pin connector is secure.

Compressor is faulty is one of the few error messages that actually says what it means. Your compressor is faulty.

Strange that when the car was low, engine running, there was no power to the compressor.

I did renew the seals on the pump when I first obtained the car three-four years ago.

Sorry, I realise that this is a bit of tail chasing, but when you went into Nano to manually switch on the compressor, did Nano report that compressor was already on? I am guessing it said off.
Next time it does this can you write down the status of pump, pressure switch, and over temp switch before you change anything?.

It could still be an intermittent pressure switch or, less likely, the temp sensor.
Although, I would think that if either of those were bad, the ECU would not allow the Nano to turn on the pump?
Of course, intermittent faults are a bugger to track down, which is why I am asking previously answered questions......Looking for you to catch a different reading.

If, when you switch on the pump with Nano, as you said, the suspension immediately begins to rise, and stays up, I am thinking that the compressor is fine.
Mine was doing much the same thing, and it was a faulty relay. It could be an intermittent connection on the PCB of the fuseboard as well. They do fail.

I will check what the actions/settings are next time...Thanks.

All has been reasonably well recently. I have been busy plus being away for a few days as well.

Used the car to move a pile of stuff from my daughters today. 15 mile drive there, all OK. Left car for an hour with tailgate open. Started up and car was low with light flashing trying to raise. Had limited time so straight on the motorway and you guessed, no rise. Damn!. Display then gave all lights flashing for a minute or two before settling on all display lights solid and warning symbol on dash...

Pulled off and connected the Nano. New fault stated, "Rear Right Valve is Permanently Closed". Hmm

Deleted fault, still no pump action. Went to settings and switched pump on manually. Totally forgot to check items in "Bolt's" post above.

Car raised at rear after a few minutes and after another several minutes, raised at front and settled level.

Remainder of journey fine!

Getting very frustrated and a friend is selling his L322, TDV8...

A valve permanently closed means that the ECU has instructed a corner to raise but it hasn't seen a change in the signal from the height sensor. Doesn't help much as it could be a leak at that corner, it could be a fault within the Height sensor or it could be that a valve really is stuck closed. Why it doesn't behave once the fault is cleared I have no idea. I assume you are clearing the fault with the engine running, switching off then starting up again so it gets chance to reset?

Cleared fault with engine running. Didn't switch off and on again...Will remember next time.

See what happens next time?

Thanks for the swift input Dave.