Use a DC test light to check for power on both sides of the fuse wile it's still in the fuse panel and the ignition in the run position and the fan switch on, the light should light on both side of the fuse if it's good, if it's burnt out it will only light on one side. If the fuse is good use the test light to see if you have power at the motor. If you have power at the motor and it doesn't work the motor has to be replaced if not you will need to start tracing the wires back to find the break in the circuit.
A DC test light can be bought at any auto parts store or hardware store for a few dollars and is a very useful tool to have around for diagnosing electrical problems in your car.