Hey everybody this is my first post and it seems like there’s a ton of knowledge on this forum so I’m hoping someone can help me out. So anyways I have a 91 k1500 and the heater control hasn’t worked since I’ve owned the truck. Yesterday I went out and started poking around to see if I could figure out what was wrong with it. I pulled the center section of the dash and glove box out and found the three wire plug that would receive power for the unit hanging loose not plugged into anything. The other side of the plug that would feed this with power is nowhere to be found. I’m figuring I’ll just cut that plug out and splice in my own plug in connectors but I’m hoping someone can clarify which wire receives what. I’m assuming the red wire gets 12v, the black wire goes to ground, and I’m not sure what the third yellow wire would be. Can anyone tell me if my assumptions are right or wrong and what the third wire would be?