Well here we have another one on my 4.8is.

I have Air Suspension Inactive message on the dash and the car is not raising or lowering. I have no sag and all four corners appear (to the eye) to be level. My ride height switch is NOT illuminating at all and the compressor is not running - nothing, dead, zilch.

I have checked all the fuses and all are good.

I have opened the boot floor and checked the radio well with zero water ingress (I have no sun roof).

Next I took the compressor housing apart. Oh Oh. The thick red & white wire was stripped of insulation where it has been rubbing on one of the retaining bolts. No burning or melting just bare clean copper wire. I have re-insulated that wire but the pump is still not running and the switch is still not illuminating.

A volt meter at the pump shows zero volts at the pump end.

So next I tried the fuseable links on the left rear of the boot floor (behind the seat in blue box with white cover) These all have continuity and all are showing battery voltage - I am assuming that these are all good.

I am told that there is a "Relay" next to the radio module and this may be bad as I have no voltage at the pump?

On calling BMW (Lookers) they were of no help and could not tell me anything about the relay or even if there is one?

Can I ask please:

Is there a relay or another fuse somewhere? I have checked the fuses in the glove box and the boot.

Given I have no power at the pump? is it likely to be the relay or is that because I have the tailgate open?