Check the control module, the resistor, etc......
Bad blower resistor?
replace heater relay and or heater blower motor
The resistor motor may have went out if the heater blower quit working on a 2004 F-250 Truck. The cost to replace the motor is approximately $200.
Blower fan resistor under glove box...by passenger's feet...!
The a/c heater blower motor resister is located in the vehicle on the passengers side inside the housing next to the blower motor...............Remove the blower motor resistor wire harness connector.Remove the blower motor resistor screws.Remove the blower motor resistor.
the heater fan resistor is located under glove box beside the fan blower.
One reason a 2004 Monte Carlo heater motor blower may not work is low coolant. You can check the coolant level after the car has been turned off.
The blower resistor assembly is located under the hood, on the heater case to the right of the blower motor. Haynes Manual #36071
The blower motor resistor pack is bad.
circuit #12 30 amp
under dash on passenger side to remove the blower moter all you have to do is unscrew 3 screws and 1 small hose and the moter and housing comes out
The blower motor is failing and will need replaced.