Hello from So Cal

I am new here. Living in Southern California.
Picked up an 89 Cressida for my daughter's use at one of those charity donation places. Bad idea.
It's a great ride but I don't know if I have ever had so much trouble from one car.

Currently chasing the lack of power to the AC clutch. When I had a shop pressurize the system, they said the pump suddenly froze up, so they discharged it. So for some time we have been running it without AC while waiting for the opportunity to do a major system repair. This week I am checking the system. AC Clutch works if I power it up with a stray wire, but the line that should supply the power does not. Appear to be no line breaks within a foot of the pump. When I power it up while engine is running, the pump spins properly. Looks like it lost power and a non-brained tech called it a freeze. I should have made him show me at the time.

I don't see any reference to a fuse.
Any ideas on how to track down the failure?