Heat and Air Temperature

[pack87]

I have a 2007 Silverado 2500hd classic crew cab. The lights on my HVAC control module went out so I ordered a replacement from Summit. I programmed according to their instructions and was only getting cold air at 60 degree setting, and heat from 61-90 degree setting. I exchanged for another and got the same issue.

 

I then ordered a factory refurbished unit from Rock Auto and followed calibration steps from YouTube that involved putting on auto mode, removing fuse for 1 minute, starting vehicle to allow system to cycle, then shutting off engine for 10 seconds and then turning engine back on. The result is heat at 90 degree setting only, all other settings from 60-89 are cold air.

 

Am I dealing with a bad controller or something else? Any help is appreciated!