My A/C on my 03 Z is blowing cold air out my de-frost vents and not out through my front vents anyone know what the problem is?

 

There's a motor in the blower housing assembly that moves the mode door, and apparently it's not working properly. You'll need to get section ATC of the service manual, and do the diagnosis for that part of the system.

 

I heard it could be a bad wire? but how do u even figure that out

 

There's a troubleshooting procedure in the SM to help you isolate the problem.

All the ***** and switches are connected to a microprocessor with little tiny wires or ribbon cables which can't carry enough current to do anything. The microprocessor provides signals to relays, which are connected to the various motors and solenoids with larger wires which can carry enough current to do real work. The microprocessor samples the position of each switch and **** several times a second to determine what needs to be done.

It's overly complicated and a ***** to work on, but it saves Nissan several dollars and a couple pounds per car.