did you/they find a reason for the refrigerant loss?
Not sure how long the system was left with no refrigerant but that can cause issues and may need a new dryer then the system drawn down to a deep vacuum as well as oil and refrigerant then added once the system has been repaired.
There's probably an ECU for the AC so worth finding out if any codes are stored which may help diagnose the issue.
From what I remember when sorting issues on a couple older ICE cars, a number of things can cause the compressor to not run:
1. Failed electric clutch
2. Seized compressor
3. Failed pressure switch
4. insufficient refrigerant pressure
5. Overpressure
6. Failed external/internal temp sensors
No idea which of the above would apply to the PHEV - its unlikely to be using a belt driven by the ICE, for example.
I assume you'd be getting this work done at a certified AC repairer, since discharging the refrigerant to atmosphere isn't legal these days not to mention any health risk if you're nearby breathing it in. For sure don't be smoking nearby if you do...
