In search of a wiring diagram for what is described in the above title. It uses a Lo-Off-Hi switch and not sure if a relay is required. Thanks in advance.

 

If you have the switch, you can make a harness. The center terminal goes to the motor. The outer terminals are power. There is a jumper harness that goes inline with the brown wire to the fan switch The low speed has a coil of resistance wire, similar to what you would find on a points style ignition system. I got my re blower from a swap meet, the harness was cut up. Instead of using the coil or resistance wire, I used a 5 ohm 10 watt resistor from radio shack. I don’t know how close 5 ohms is to the original harness, but there is a noticeable difference between low and high. It works well, and has worked for 20 years.

 

Thank you. This is very good, detailed information. Looks like you really have a handle on how to correctly wire this unit. I'll see what I can make happen.

 

I don’t recall ever seeing a wiring diagram in the service manual. There is a few photos in the assembly manual showing the jumper harness.