The HVAC blower motor resistor controls fan speed by reducing voltage to the blower motor. When it fails, some or all of the lower fan speeds stop working.
Common Symptoms
- The blower works only on the highest setting.
- One or more fan speeds do not work.
- No blower operation at all on some designs.
- A melted or corroded connector.
Why Resistors Fail
- A worn blower motor drawing too much current, which overheats the resistor.
- Corrosion from moisture in the HVAC case.
- Poor connector contact causing heat buildup.
Replacement Tips
- Check blower motor current draw or condition before installing a new resistor.
- Inspect and replace a heat-damaged connector.
- Test every fan speed after installation.
Evergreen Parts
Evergreen offers other parts identified by engine or vehicle application. Use the Evergreen eCatalog to find the right part, and see where to buy Evergreen through our authorized distributors.
