This has nothing to do with Electrical Installation. These photos link from Volvo forum

http://www.volvoforums.org.uk/showthread.php?t=7719&highlight=compressor

the views are from underneath the vehicle looking up.

View from below. Gap between clutch plate and pump was 1.1mm

Having removed the belt and 4 mounting bolts it is possible to tilt the pump to get access to the clutch plate. I removed the bolt securing the reservoir container bracket (from above) so that it could be moved and held forward with PVC insulating tape, giving much needed room.

Using 2 M5 screws and a screwdriver to stop the plate rotating whilst undoing the centre bolt.

 This is the puller I made. 6mm holes in a 33mm equilateral triangle. 40mm x M5 studs, nuts & washers and a 40mm x M6 bolt.

The puller is up against the 6mm bolt head protruding from the centre of the plate. Surprisingly little force needed to tighten the nuts to get the "pop" indicating that the plate was loose. 

A further half inch of screwing required to get the clutch plate off and remove the puller & centre screw.

The inside face of the clutch plate and the 3 shims, each a different thickness.

The inside of the clutch.

Re-fitting the plate needs quite a lot of force.

Gap checked - now at 0.5mm

on a warm sunny afternoon, blowing cold air with A/C off - 19 degC 

a minute  later with the A/C on  7.9 degC

Temp reduces with higher engine revs.