89 TRX 350D cooling fan

I’m new to the forum. I’ve had a 89 TRX 350d for a long time now. I’ve had no issues until now. The oil temp light comes on when I’ve been riding for a while but the fan won’t come on. I’ve read through the service manual and tested the wires going to the fan control unit. I have power going to it. I took off the oil temp sensor wire and grounded it to the frame and the fan will not start. My motor is not seized on the fan. When I ground out the oil temp wire should the oil temp light come on? It’s not and the fan won’t start. I’m guessing my wiring is fine, just trying to figure out if the fan control unit is bad or just the fan motor? Can I put power directly to the fan motor to see if it will turn? Also where can you buy new parts for these old machines? Thanks!

Kelvin