Hey everyone, I am having trouble figuring out what is up with my heater blower.

when I turn it on some buzzer sound starts to go off, and it doesnt turn..

if i hit the a/c button the buzzer changes tone, but not blower movement.

I pulled the blower out and hooked it up with dome test leads to the battery and it turns like a champ. I cant figure out what the deal is. my haynes manual doesnt have anything related to the heater motor other than how to remove the blower.

any help would be greatly appreciated. thanks,
bill

 

Buzzing sound from an electric motor usually means its stuck. Is there anything the blower motor gets stuck on when its installed in the truck? Maybe some debris?

 

What year is your truck? Can you tell where the buzzing is coming from?

Normally, if the blower motor works on high speed but not one or any of the other speeds the blower motor resistor is to blame - you don't have anything though?

 

Might be the relay for the blower, look up under the dash, passenger side in the center for the relay and fuse for the fan. Probably have the relay coil buzzing, should be able to feel it with a finger, but touch carefully because it may be hot as well.

 

My runner did that but it was the resistor and actually had gotten hot enough it melted in the plastic. Replaced the plug and resistor and plastic that was melted and works fine.