No Horn

03 AV keeps blowing fuse. also notice that the light for the driverside temp control is out. Does anyone have a wiring diagram for this? or know what else is in the same circuit? I don't notice anything else off. thanks

This truck has two horns. One behind each front turn signal lamp. They have a bad habit of collecting water. I bet one, or both, have water in them. After looking at the schematic, the only way it will blow is if the horns are drawing too much amperage (assuming the wiring is good). Like one with water in it. GM came out with a snap on cover for the horns to try to keep water from getting in. My suggestion, unplug the horns at the horns, replace the fuse and try to blow the horn. If the fuse blows, you have a wiring problem, if not try plugging in one horn at a time and retesting to see if the fuse blows. Which ever one you plug in and then the fuse blows I would replace. Make sure you are getting the correct one. Look closely and you will find an "L" or "H" within a circle on the side of the horn near the trumpet end. Make sure you get the correct one if you get to that point.

As far as the light out, I assume you are talking about the back lighting on the dash mounted air conditioning control head. There is not a separate circuit for this. It is internal to the unit. No repair but replace. If you have automatic air (lcd screen in the center) it has to be programmed by the dealer after replacing, it's not plug and play. If you have the manual (two up/down sliders in the center), it is a replace and disconnect the battery for 3 minutes to recalibrate the ac system. Hope this helps.