blower motor resistor

Replaced the automatic climate control. The unit worked fine for a bit and then the blower motor stopped working. Replaced the blower motor and it worked fine again for a couple days. Blower motor stopped working after a couple days. Auto climate control unit appears to function the way it...

I have 02 tahoe and it has the heater control with the auto feature. Anyhow if it's set all the way to cold, cold comes out but if I turn it 1 click above cold.... Hot air trickles out. I can't make any type of warm air at all. Need help diagnosing it please.