The blower motor resistor on a 2001 Prism controls the speed of the blower motor, which in turn controls the amount of air that flows through the vehicle's vents. The resistor works by varying the amount of resistance that the blower motor has to overcome. When the resistor is set to a low resistance, the blower motor can draw more power and run at a higher speed. When the resistor is set to a high resistance, the blower motor has to work harder to overcome the resistance, and it will run at a lower speed.
The blower motor resistor is located in the passenger compartment of the Prism, near the blower motor. It is a small, black box with a few electrical connectors. If the resistor is faulty, the blower motor may not work at all, or it may only work at one speed.
