Chevrolet Repair: Passenger side blowing heat during a/c mode, c mode, wrecking yard

Question
(04 tahoe)During a/c mode the heater is blowing only on the passenger side
while the driver side a/c is working fine.Is there some type of relay or possable
fuse?If so where can I find a diagram.Thanking you in advance

Answer
Hi Mike....most problems that are heat/cold related usually end up being the heater control panel...because the panel has a printed circut in it...the fasted way to see if thats where your problem is would be to go to a wrecking yard and find a known good one and try it...if it doesn't cure the problem then you will need to look deeper...also check to see if something hasn't fallen down thru the defrost vents and is jamming the door that controls hot and cold...i have found all kinds of stuff down in them....kids toys, change, pens, hope this helps