My task is to bypass the internal pcb on this air conditioner to allow power to the external unit. Currently the external unit receives no power except a small current from the comms wire. The goal is to allow max cooling, temp control is not necessary.

 

It could be done on old units but all the modern stuff has speed controlled compressors and variable eev valves (bottom left) which need the processor to be in the loop.
I had one years ago that wouldn't run because the thermistor had gone out of range, it ran if I warmed it up so as a temporary fix I stuck it to a little warm transformer on the pcb, maybe you can do something similar.