NO AIR coming out of vents (ac/heat)

[Fless]

You can watch the whole thing, or from where it starts. He shows how to test a J-case fuse with an ohmmeter. You can also use a visual test but those aren't always absolutely accurate.

 

[Doubeleive]

it used to be on the previous models the fan blower motor resistor would go bad and then you would get a variety of problems, no fan at lower speeds, or fan on when key off, or any combination. now on the gmt900's they overbuilt the resistor and I don't see any complaints of them going out, so that being said "IF" a fuse blew there is a reason why, I would start with checking the fan motor, if you do not have any technical tools or skills then I would just remove it and apply 12v directly to the motor to test it or if you can run a couple wires to the motor connector, to get access to it you will need a 7mm deep socket, it is under the passenger side kick panel under the glove box, there are lots of youtube videos showing how to replace the actuator the fan is right next to it and it is in the same location for like 20+ years now.