[xf_phil]

There isn't one, it's controlled by a high side driver in the RSJB.

 

[xf_phil]

Well I'd not expect it to be live all the time, only when the system decides to run the compressor, it generally waits until you're doing just over 30mph ( so you don't notice any noise from it ) and then runs it if the pressure in the reservoir is lower than desired - and even then it probably only turns the output on if the automated checks for open/short circuit at ignition on time passed.

What problem do you have with your air suspension?
Have you read the fault codes with something that reads full 7 digit codes from all modules?

 

[xf_phil]

As I won't be around much if at all tomorrow, I thought I add.
If the car is at normal height, but you get a air suspension message on the dash when you reach around 30mph and have the code C1A20-64, then it's quite likely the compressor has failed ( or at least the seal on it's piston has ). See https://www.jaginfo.org/posts/2843843/

 

[xf_phil]

That code if for short to ground.
What make and model of pump did you buy?
I suggest you unplug the compressor, and the black connector on the rear junction box ( circled in green in my post I linked above ). Then use a multimeter to test resistance between there and battery negative, it should be "infinite" i.e. open circuit. Also check the resistance between the pump contacts while it's disconnected, given the 380W rating of the pump I estimate that should be somewhere in the range of 0.4-1 ohm.

 

[xf_phil]

AMK BIL10-309483

Well at least it's a decent make, as far as I know it should be AMK A2830 though, perhaps the one you got is designed for a different car and draws more current so the rear junction box has decided it's shorted due to lower resistance.

I suppose it's maybe just suffered an early failure, did you check the resistances as I suggested?

Has your car had an issue with water in the boot?
If so, did you dry the foam intake/exhaust filter?