Why Blower Motor Resistors Are Necessary

Why Blower Motor Resistors Are Necessary

The blower motor pushes air through the vents - the resistor controls the motor's speed. Sponsored by Standard.

When the heat is on, your customer’s HVAC system needs to be up to the task. The blower motor is like the heart of the HVAC system, pushing air through the vents to cool or heat the vehicle cabin. But we need to control the blower motor speed because no one enjoys hearing that fan spin at full blast, right? 

So, if we apply 12 volts to the blower motor, it will spin up to its maximum speed and stay there. That’s where the blower motor resistor comes in. Resistance in a circuit changes some of the electrical energy into heat and causes the blower motor to spin more slowly. 

But, let’s be clear, the blower motor resistor is the only place you want to find resistance in the electrical circuit. Improper harness connections can cause resistance and generate heat. This can eventually cause the wires, pins and/or the connectors to melt. 

There are other potential causes of resistance in the circuit. A failing blower motor, a fan cage which is damaged or full of debris, a clogged cabin air filter, all of these can cause the blower motor to have to work harder, draw more amperage and generate more heat in the circuit. 

Standard offers a full line of more than 770 blower motor resistors for import and domestic vehicles. These high-quality blower motor resistors are manufactured in Standard’s IATF 1649-certified North American facility, and are designed to match the original for easy installation and correct performance at every fan speed. On top of that, Standard engineers sample test every blower motor resistor for draw, resistance and RPM to ensure proper performance and reliability. 

In addition, Blue Streak is proud to offer premium Blower Motor Resistor Kits as a high-quality solution for melted connectors and blower motor resistors. Blue Streak improves on the OE design to create a connector that withstands excessive heat, reducing failure. Each kit includes the needed blower motor resistor and problem-solving high-temp connector for a complete repair solution and is backed by the Blue Streak Limited Lifetime Warranty. 

This video is sponsored by Standard.

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