Blower Fan Motor Works On High Speed Only
All cars are designed with a blower fan motor that pushes air through the ventilation
system. This air is processed by a series of vents to direct the air to various
positions. Example: heater,
air conditioner and defrost
modes. Most blower motors are powered by a basic electrical circuit that utilizes
a multi resistor or a solid-state resistor to control different fan speed modes
(low, medium low, medium and high). If the resistor malfunctions it may lose one
or more of the lower fan speed settings.
TroubleshootingTurn the key to the "on" position (do not start the engine). Inspect system fuse and replace if needed. Some cars utilize separate circuit fuses in the fuse box, be sure to inspect all fuses and replace as needed. Remove the fan speed resistor component.This resistor is almost always located in the heater plenum so it can be cooled by the air circulating through the vents. After the resistor is removed inspect the resistor for obvious burn marks at any point. If any area shows signs of extreme heat it needs to be replaced. Also inspect the resistor connector for heat damage. Reinstall with new and recheck system.
If further technical assistance is needed, our certified car repair technicians are ready to answer your car questions. Related Car Repair Information
TroubleshootingTurn the key to the "on" position (do not start the engine). Inspect system fuse and replace if needed. Some cars utilize separate circuit fuses in the fuse box, be sure to inspect all fuses and replace as needed. Remove the fan speed resistor component.This resistor is almost always located in the heater plenum so it can be cooled by the air circulating through the vents. After the resistor is removed inspect the resistor for obvious burn marks at any point. If any area shows signs of extreme heat it needs to be replaced. Also inspect the resistor connector for heat damage. Reinstall with new and recheck system.
If further technical assistance is needed, our certified car repair technicians are ready to answer your car questions. Related Car Repair Information