the fan is under the glovebox. if you look under there you'll see a circular black plastic base with 3 tabs that the screws go through to secure it to the heater assy. it has a plug in it. remove the plug and put a test light between the 2 wires. turn the key to the on position(engine not running), and turn the fan on. the light should come on in all 3 or 4 fan positions. if it does remove the fan by taking out the 3 screws and replace it. if the light wont come on in any position, you probably have a blown heater fuse or a bad switch. if the light only comes on in the high position(in this case the blower would also have worked on high i suspect) the blower resistor is bad. its a small plate(1 1/2"x2 1/2") on the heater near the blower held in with 2 screws. just remove the screws and replace it to restore the lower blower settings.