Heater blower wont work. what would it be

turn swich on key on tap on back center of fan test light

Most likely the ballast resistor located under the dash on the heater housing.

I have an 08 Grand Prix Base Model and my blower just randomly shut off last night and it has to do with the harness connection behind the radio. I took the panel off from underneath the glovebox (where the blower motor is in the passenger side floor board) and also the panel on the right side of the DIC, radio, and climate control (had to open glove box to get it off). Well I ran my hand along the wire to route it and came up to a connector for the blower motor, directly underneath the center dash air vent. I'm assuming that all of the heat coming from that vent is damaging the connector. I shook the wiring harness and the blower motor work, but if it moves or shakes then it goes back off. Sorry if I seem like I'm rambling, but just wanted to feel you in on what is going on with mine.