Blower Speed Control

WARNING: This page is about a different car, the 1999 GMC Sierra and 1999 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.

The blower switch provides a choice of various blower speeds. A fuse in the fuse block provides power to the blower switch when the ignition is turned to the ON position. In the low speed position, the circuit continues through the heater wiring harness to the 4 resistors in the resistor assembly. The resistor assembly is near the blower motor.

When the blower switch is in the medium speed position, the circuit continues through the heater wiring harness to the resistor assembly. This circuit then bypasses 1 or 2 of the resistors.

When the blower switch is in the HI position, the circuit continues through the heater wiring harness to the resistor assembly. The circuit bypasses all 3 resistors in order to provide full power to the blower motor.

From the resistor assembly, the circuit goes to the blower motor terminal in order to operate the blower motor.