To replace the car heater blower motor, first remove the old motor by disconnecting its connector and unscrewing the screws that secure it in place. Then, install the replacement blower motor by attaching it to the heater case or firewall and replacing the connector.
Begin replacing the blower motor of a car heater by disconnecting the negative cable from the vehicle's battery. To do this, undo the retaining bolt with a wrench, and remove the clamp from the terminal.
Then, identify the blower motor in the car. Normally, it is located within the engine bay on the firewall on the vehicle's passenger side. Sometimes, it is located within the passenger compartment, beneath the dashboard on the vehicle's passenger side.
To remove the old blower motor, disconnect its plastic wiring connector. If the motor has more than one connector, mark them to make reassembly easier. With a socket, remove the motor's screws. Then, detach the motor along with its fan blades from the car. Remove the screws that attach the motor to the fan blades, and separate the blades from the motor.
To install the replacement blower motor, screw the fan blades to it, position and screw it on the firewall or heater case, and replace the plastic connector or connectors. Then, connect the negative battery cable, and replace the clamp and the retaining bolt. Finally, test the new motor for proper installation.