more than likley it is the blower motor resister it should be located next to the blowere motor "
Underneath the dash on the passenger side, you will see a metal plate with a wire clip and 4 wires leading out... (it's shape is sort of a cross between elliptical and diamond) remove the wire clip and you see 4 metal tabs. Remove the 2 bolts and the resistor is attached to the other side of the plate.
You must first remove the glove compartment to see the resistor" the info in the quoptes is for a 99 but shouldnt be too diff check the electrical conter for the blower motor resistor most of the time it gets burnt and loses contact take a look there to see if that is the cause
does any speed work on the control?