switch contact"s
When you find out let me know I have same problem replaced blower fan and resisitor did not work. I have a blazer zr2 2002
If the position #5 (high) blower is not working, it is the small resisitor assembly on the blower motor housing under the passenger side dash. Very easy to replace.
If the one speed it works on is high speed, it is the blower motor speed resisitor that is bad.
It is located on the passenger side firewall in the engine compartment, right next to the strut housing.
This is Jim. Thanks but I finally got it off and the heater fan NOW works.
Attached to the blower motor under the passenger dash
The bearings are out of it. Replace Blower motor.
The blower motor is drawing to many amps, replace the blower motor.
You either have a blown fuse, defective blower motor, defective blower motor switch, or a defective blower motor resistor pack.
blower resistor is bad
Most likely your blower motor resistor is bad. I replaced the resistor and the blower motor fan and it ended up being the speed control switch (alot easier to replace than the resisitor). Both the resistor and switch are around $19.
The blower motor resistor is located under the glove compartment in a black shroud.