Buzzing Noise when Heater is Turned On

Anyone have a solution to this problem. When I turn my heater on there is a buzzing noise coming from behind the glove box. It is clearly an electrical noise. It does not get louder when I accelerate. It makes a buzzing sound for approximately 15 seconds, and then goes mute. It is very annoying.

My local mechanic said that it was a resistor or blower motor resistor, if I’m remembering correctly.

Solutions or thoughts? I want to do this job myself rather than take it to my mechanic. Thanks!

 

drop the blower and make sure theres no debris in it.

While in there, check the connections. Any that look or smell burnt need replacement.

 

If your fan works on all 3 speeds it's not the resistor.
Start by removing and cleaning the fan.
The fan motor is behind and below the glovebox. Unclip the elect connection and remove the 3 screws to lower the fan and motor for cleaning.

 

It's probably the servo for temp control. Small plastic box on passenger side under radio. Easy to replace and can get aftermarket at auto parts. Just looked it up. Blend door actuator. I replaced blower and didn't fix noise. Replaced actuator and all good

 

Thanks y’all I’ll start with those options and see what shakes out. Appreciate the feedback!

 

Yep, It’s gotta be the servo temp control/ blend door actuator. The noise is definitely coming from that contraption. Ordering one stat.

 

Maybe there is a dedicated fuse you can pull to test