heat failure driver's side 2006

if I am right, you have climate control for both the passenger and driver on that truck. There is an HVAC unit that controls that function. Often, they fail over time and you will either get scalding hot air in the summer, or freezing cold air in the winter. A temp trick is to start the truck, turn on the climate control at max "auto" position. let it run for 30 seconds. then, without touching that cliamte control, turn off the truck, take the keys out. Disconnect the battery for about 1 minute, this will allow the trucks computer to reset. then, reconnect the battery, start the truck, then just touch the "auto" button on the climate control, and let it run and see if that solves the problem. If that doesnt work, you may need to take it to the Chevy dealer and see what code it is calling out for. If it is the HVAC sensor unit, buy it on Ebay (which should save you $200.00, and have a good machanic install it.