C5 x7 suspension pump running intermittently when parked

[rogerc5]

Hello folks
This one is puzzling me .
My 10 reg x7 suspension pump runs randomly when I park the car with ignition off.
It doesn't seem to be under load or correcting the height, as happens when I turn on the ignition, and can be interrupted by flashing the lights or opening a door.
It does stop after a while and doesn't seem so far to be compromising the battery.
I am told it could be the rear height corrector, which is scheduled for replacement and was fairly rusted up.
Anyone have views on this please?

[EDC5]

Does it only run for a few seconds? Mine has always done a final adjustment once it was locked and I'm walking away.

[rogerc5]

Not just a few seconds- it starts and stops and starts again and can go on for a few minutes.
Any electrical activity can stop it for a while, like opening a door etc.

[GiveMeABreak]

Hi Roger, this can be attributed to a faulty height corrector. But it may be normal behaviour as the vehicle monitors the height even without the engine running. Normally with the doors open or when you are loading the boot, the pump will kick in to adjust the height.

It's when in the morning for example, when the car is unlocked, the suspension ECU performs a height check and correction if necessary as the circuit is woken up, triggered by the unlocking in anticipation of the vehicle starting a journey. Sometimes after a trip when the vehicle is at rest, it can make slight height corrections too. This can depend on the road conditions previously.

However, if the pump is running for anything other than say 5-15 seconds with the engine off after the doors are closed and the car locked, or if the car is idling, then I would say that could be indicative of the suspension ECU operating the pump trying to correct the height.

Let's say that normal ride height is a hypothetical value of 50 and the height corrector is faulty and sending a value of 48, then the suspension ECU will be operating the pump and waiting for the height corrector to report '50', which it may or may not do. It may be reporting 48, then 50 then 51, 52, then 49 etc., causing the pump to operate to raise pressure or the electrovalves to release fluid back to the reservoir.

Sit may be worth keeping an eye on and you can also try raising the car to maximum height, the lowering to the lowest and repeating that a few times - but not too many as you don't want to overheat the pump - they are only designed to maintain / top up pressure under normal running conditions.

[rogerc5]

Thanks Marc
Malcolm at Savoy is going to fit a rear height corrector soon to see if that cures it.
It's weird how opening a door stops the pump for a few secs- almost like breaking a circuit.
Still- a nice car!

[Hell Razor5543]

It's weird how opening a door stops the pump for a few secs- almost like breaking a circuit.

It is possible that the car, seeing that a door has opened, is waiting to 'see' if that has affected the level of the car.

[rogerc5]

Hello everyone and thanks for all suggestions.

After fitting a replacement rear height corrector the problem did not immediately go away, but after a period of regular use and some long distance trips I think I can say it's gone.
There I said it; hope X7 can't hack my PC!!

Thanks to Malcolm at Savoy for his endless enthusiasm and patience.