Just to confirm, you had no power at the compressor and when you jumped 12 volts to the compressor, it still did not come on? If that is the case, we are missing something with that.
Take a look at this wiring diagram. You should have power on the green wire at the compressor when you jump the relay for pin 30 to 87. So if you remove the relay and jump those two pins the compressor should come on.
If you have no power and when you give it power and it doesn't come on then we are not doing one of the two correctly. If you are then I get your confusion. Maybe get some pictures or a video of how you are testing for power at the compressor with the engine on and A/C on. Then when you are jumping power as well.
Basically the way this works is if you turn the AC on, the HVAC module should have the low pressure circuit grounded. If it does then it sends a signal to the PCM. If the PCM gets proper signal from the pressure sensor and signal from the HVAC control module, it grounds the relay and the compressor kicks on. Then it will cycle the compressor based on the pressure sensor reading.
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Friday, April 30th, 2021 AT 4:03 PM