Non-blowing heat and A/C blower fan.

Try to check the power and ground on the blower fan. If you missing the ground on the blower fan connector than most likely it is the blower fan resistor (controller), it is located under the hood close to back firewall behind left cylinder head.

Sounds like high blower relay is bad

in review
the fan speed resistor is new
you bench tested the blower motor
12 volts test ..only runs it at full speed
if cabin filer want changed the blower motor would run hotter

could be the motor brushes or bush/motor bearing when slowed
you might want to inspect the brushes and clean the dust out of the motor
if no better
does that have climate control ?
might be the fan switch itself or the earth isnt so good

is the fan working in all speeds?could be a fan resistor if not or cage on blower motor restricted some how thats what i would check first

Usally when a blower motor resistor goes bad the fan still runs on high. The resistor lowers the voltage going to the fan to make it run slower. The high setting usually goes straight thru. Resistors are usually easy to get to, under good on the firewall or under dash passenger side. Cost about $24 at parts store. Replace with new if that doesn't work return it.

I had the same problem. I fix it my self. This is what you look for, is your a/c blower working when you turn the fan on. If a/c light come on but nut the blower fan. Then under passenger dash you will see orange plug. It's held in with 2 screws. Remove 2 screws and pull resistor out. Disconnect orange plug and look at orange plug and the resistor if burn need to replace the resistor and the orange connector. That's your problem. Now if your blower works but no power to a/c switch and you instrument nobles has no lights. Then it's a fuse check #48 and # 57 fuse that controls that Troy

Its either a bad connection on the blower motor resistor or a faulty blower motor resistor.These are known for over heating.

your blower motor may be drawing too many amps causing the heat problem at the plug. If so replace the blower motor. and / or The connector plug to the blower motor resistor will melt causing it to fail. you may have to replace the blower motor resistor plug (pig tail). Lastly check your blower motor relay. Making sure you are getting full volts accross the contacts..

You don't list the vehicle your asking about but in general when the blower motor only works on the high speed the blower resistors have blown. The resistors are what control the fan speed, when they go bad only high will work. The resistors blowing is usually a side effect of a blower motor going bad, pulling too much current. When replacing the resistors it's advisable to replace the blower motor as well so as not to have a repeat problem.

Replace the blower motor resister,it is mounted right next to the blower motor,it has a lug with about 7 wires on it.Just unplug it and remove two screws to remove the resister.This controls the speeds for the blower motor.The blower motor is the cause of the resister failure.Even if the motor seems to sound,and run fine,it is pulling to many amps.