MY 2003 YUKON JUST STARTED BLOWING OUT HOT AIR ON PASSENGERS SIDE AND STILL BLOWS OUT COLD AIR ON DRIVERS SIDE. JUST HAD BATTERY REPLACED. WOULD THAT AFFECT ANYTHING?
according to GM on the right side of your dash there is a connection junction block that might have issues like back out terminal or shorted wires, but I have experienced the temp actuators that control the temp to each side of the vehicle will seize at time and will need to be replaced. Hope this helps.
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