AC fan only blows when high setting button is pushed none of the other buttons gets it going.

The thermistor controls fan settings. On high, the thermistor is not needed (bypassed) and the fan motor runs at full speed. On lower settings the voltage to the motor is stepped down by the thermistor. If it goes bad, those lower settings wont work. You can access the fan motor under the dash, beneath the glove box, by removing a panel. The fan is plugged into the thermistor and the thermistor plugs into the wiring harness. A parts store can help you find the right one, they are fairly easy to replace. A blower motor that only works on high is almost always a sign the thermistor is bad.