Okay, I looked on the web and found a diagram for a Single Phase 2 Speed electric motor.

It shows a center off rocker switch with the Phase (hot) line coming to the switch. In one (side) position it connects the Hot to the red and in the other to the black, both return via the white to the neutral. Thus, if the return/white is broken (in the subject motor somewhere inside the motor) one would read a resistance between red and black, and an open between white and either of the the other two.

Typically, two-speed appliance motors use a white for neutral, red for low, and black for high.

As long as you are comfortable doing this, use a zip cord with a plug on it, stripped at the other end and attached with wire nuts to each combination.

If I'm checking an unknown motor, I usually will plug it into a power strip with it's own breaker in case there is a fault in the motor - it will usually trip faster and with less smoke. :)

Thanks that fits with my thinking/analysis and web findings. I had not interpreted far enough to determine which color was which speed.

I think your test method would work well. I sometimes put a low resistance, maybe a 200 watt bulb (or 1 ohm high wattage resister) in series with such a test arrangement, then if the motor, say, is shorted the light will light and the current will be limited to less than 2 amps for 120 volts.

I decided based on my ohm meter reading to order a replacement fan. Some one told me they had seen a not replaceable thermal or current (fuse) under the wrap in the white return that was blown/burned out. I started to cut into the wrap but quit as it looked like I might cut some wires in the coil that would further damage the unit. I will hold on it for a while in case my interest increases enough to tear into the motor.