Where is the Car Blower Resistor Located?
2 Answers
Car blower resistors are installed and fixed inside the air ducts, allowing them to be cooled by airflow when the blower is operating. Blower Working Principle: Whenever the blower is running, current passes through the speed control resistor, causing the resistor body to heat up. The resistor body is equipped with a fuse. If the blower becomes blocked, short-circuited, or experiences abnormally high current, the fuse will blow, rendering the blower inoperable. Main Function of the Blower: The primary function of a car blower resistor is to regulate the speed of the airflow. In some vehicles, the blower resistor controls the blower's rotational speed. If the blower resistor fails, the blower may lose its speed adjustment capability, operating only at maximum or minimum speed.
A few days ago, the blower in my old Passat suddenly only worked at the highest speed. The mechanic taught me to look for the resistor. This part is usually hidden deep in the dashboard, near the blower. I looked under the passenger side footwell and found the blower next to the cabin air filter. A small metal box with heat sinks and several wire connectors attached to it—that's the resistor module. The mechanic said it often fails due to prolonged exposure to high temperatures, and replacing it requires removing the glove box to access it. German cars love to hide it here, and you really need to crouch down to remove it. Doing it yourself definitely requires a flashlight. After the repair, the mechanic also reminded me that abnormal noises from the blower could also cause the resistor to burn out, so it's necessary to check the fan blades as well.
