I have an Home AC Unit. Though the compressor turns on the fan will not. Please read my further comments.?

I tested the capacitor to see if that could be the problem. It is a dual start capacitor, with both the compressor and the fan hooked up to it. I don't have a capacitance tester so I used my multimeter and tested the ohms. Both portions of the capacitor started out at 0 and as they charged from the multimeter went to infant ohms as expected on a good capacitor. The capacitor does not appear to be blown or bubbled at the top though it is extremely rusty for being only 4 years old. I also pulled the fan motor off the AC Unit and checked the resistance in the motor. There are only 3 wires coming out so I tested all three which added up to what equates to a good motor. Beyond this I just can't figure out why the dang fan won't start. The bearings on the fan seem fine as well. They do not feel seized up. The blade spins fairly freely. The only thing I can thing is to check the relay swith. How can I tell if that is bad?