1990 Mercedes-Benz 300SL Q&A
1990 Mercedes-Benz 300SL Question: heater blower motor
There is a blower motor speed module that controls the speed of the blower motor , I would inspect that. The wires from the blower motor get power and ground from that component. - dandd
...han a defective motor, a bad switch or blower motor resistor assembly can cause an inoperative heater blower motor.