Can you seal off the lines coming off the compressor to see if it will hit set pressure and stop?

It sounds like the pressure relief valve isb opening early i think it operates at about 150-160 psi

I have no idea how I'd do that.

The line coming off the compressor doesn't have the hex nut adaptor, it's a different fitting.

Investigating further,

Both SLS fuses are missing the second contact i.e. they don't do anything.

No visible wires behind missing or cut so far.

Sounds like different version of fuse panel. Look at the other fuses same amperage


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It seems that the rear fuse section has power bridges for items yet nothing, no second wire, for the SLS fuses 79 and 87

I would pull all the 30a fuses and ohm to the compressor/relays see where it's getting fed


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I've pulled every fuse and no continuity to the live power on the compressor.

What year?


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2004 build

Ok the fuse panel has absolutely nothing to do with the power supply for the air compressor despite whatever labels are on it.

From ISTA it's connected to the main fuse bus in the boot neat the left rear air suspension accumulator.