Auxiliary Medium Blower Speed

WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2003 GMC Yukon XL, 2003 GMC Yukon, 2003 Chevrolet Tahoe, 2003 Chevrolet Suburban, and 2003 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.

When the Medium blower speed is selected at the front auxiliary HVAC control assembly, the front auxiliary HVAC control assembly applies a ground to the auxiliary medium speed blower motor relay through the auxiliary blower motor medium speed control circuit. When the relay closes its switch, voltage is provided by the battery positive voltage circuit. Voltage is divided between 1 series resistor in the auxiliary blower motor resistor assembly and the auxiliary blower motor to achieve the desired blower speed. The auxiliary blower motor is included in the series circuit by the auxiliary blower motor supply voltage and ground circuits. The auxiliary blower motor switch and auxiliary blower motor are grounded by the ground circuit.

When the Medium blower speed is selected at the rear auxiliary HVAC control assembly, the rear auxiliary HVAC control assembly applies a ground to the auxiliary medium speed blower motor relay through the auxiliary blower motor medium speed control circuit, the auxiliary blower motor switch control circuit, the auxiliary HVAC control processor, then through the Aux. CNTL switch position on the front auxiliary HVAC control assembly. When the auxiliary medium speed blower motor relay closes its switch, voltage is provided by the battery positive voltage circuit. Voltage is divided between 1 series resistor in the auxiliary blower motor resistor assembly and the auxiliary blower motor to achieve the desired blower speed. The auxiliary blower motor is included in the series circuit by the auxiliary blower motor supply voltage and ground circuits. The auxiliary blower motor switch and auxiliary blower motor are grounded by the ground circuit.