Chevrolet Heater Control Switch

I have a 1991 Chev Z71 1500. I have tried three different switches and none of them work. There seems to have no power to the switch, display does not light up. I have checked the plug from the truck and two of the plug holes have power. Can anyone tell me if that is correct and what else I can check?

Fuses?

Are we talking about the "Fan " switch. If so do you have any speeds working on the fan, or are a few speeds not working.

Yosemite

I’m talking about the A/C heater switch with the LED display. I have unplugged it and have power to two holes on the plug.

Here is a print of the switch.