NO POWER TO COMPRESSOR 1999 S 70 VOLVO CONTROL HEAD WORKS AND FUSES AND RELAY ALL GOOD NO POWER TO COMPRESSOR

check your PGMFI (Fuel Injection Main Relay) if it's good then check the Fuel Pump for power with a probe tester. what do fuses 30 & 31 operate? maybe there is a short and maybe it has to do with those 2 fuse lines working against each other or maybe they are bumping heads with the injectors electrical wiring. my first advice is to check the fuel injection main relay and the fuel pump first.

the compressor clutch is not working because there is no power supply
the ac switch may nit be working
check that the blower switch doesn't have to be on as well
the thermostat controls power to the compressor ( switches it of when cabin temp is reached
If you have climate control , check the climate control module
lastly check the fuse for the ac system

pull switch if no power back track to find open if power switch is bad the a/c relay runs the compressor a/c fuse powers relay fuse is powered by the ecm , ecm gets command from control switch, ecm reads all input and powers relay to send voltage to compressor. wire should go back to fuse box and be hot with key on.

Not a Volvo expert, but there is a low pressure switch that could be faulty, something going on with the control on the dash, and the a/c compressor clutch could be faulty.
You need to see if you have voltage at the a/c clutch then work backwards.

this control is controlled by the computer. make sure your a/c relay is good along with fuses. check the high pressure switch connection on back of compressor it may need to be put on a tech 2

Your AC mechanic is a know nada POS. Your AC is not working because the clutch is not being properly energized so as to turn the compressor which as you indicated is working and fully charged. Either the climate control head you just got is no good, ditto for the low pressure cut off switch, thermostat.. Best thing to do is get a hold of someone who has the AC schematic and can check out all of the electrical components in the way of getting power to the clutch!

There should be a relay that controls the headlights. Probably more than one. If you find the relays for the light, pull that relay and replace it with one from another light. If the light comes on then the relay needs to be replaced.

have you checked all the fuses under hood in black box? relays may be good but theres no power or that light should come on. if all your fuses are good then may be that the heater control panels bad. i would make sure that the compressors plugged up, check all those fuses, then go towards a bad heater control panel.. hope this helps!!

power comes from fuse 6 to control head then to low and high pressure switches

the climate control head is bad