duel zone AC and the driver side does not blow cold air but my pass side does

QUESTION:
I have a 2002 Chevy Monte Carlo SS 3.8v6. My duel zone AC and the driver side does not blow cold air but my pass side does

ANSWER:
It sounds like you blend door is sticking in the heat mode. It should close and a lot times it stays open and this will not let the ac come through. To replace this door the dash has to come out. It is part of the case the holds everything together.