AC Cuts On and Off Randomly

So I haven’t had my 4Runner very long, but I’ve had a few issues with it.
First being the AC randomly turns on or off by itself completely. It doesn’t matter if I have the heat on or defrost or nothing turned on at all (as in the fan/temperature control/heat - everything switched to off) but all of a sudden the AC comes on full blast. Sometimes I can get it switched off, sometimes I can’t. Sometimes the control knobs work and other times it’s like they are there for decoration. They do nothing at all.
Anyone have any ideas what this could be?!

 

Is this an automatic AC or manual?
Any codes from the OBD?

 

Manual. No codes

 

If I were to wildly guess I’d bet poor electrical connection/issue with the climate control box itself- if you’ve got a junk yard around you you could probably pull one for like $5

 

My next step would be to check the heater/AC control assembly (you'll need the shop manual) to see whether it is faulty or not or as the previous commentator has noted, replace it. Personally I'd rather make sure a part is bad, before replacing it.