Auxiliary Medium Blower Speed

WARNING: This page is about a different car, the 2002 Pontiac Montana, 2002 Oldsmobile Silhouette, and 2002 Chevrolet Venture. However, it is still accessible from the selected car via links, so may be relevant.

When the Medium auxiliary blower speed is selected on the auxiliary blower motor switch, voltage is delivered from the fuse block to the auxiliary blower motor on the ignition 3 voltage circuit. The auxiliary blower motor speed control circuit delivers voltage through the auxiliary blower motor relay and through the auxiliary medium 1/2 blower motor control circuit. Voltage is reduced by an in-line resistor in the auxiliary blower motor resistor assembly to achieve the desired blower speed. Ground is provided by the auxiliary blower motor medium speed control, auxiliary blower motor switch and ground circuit. When the Medium auxiliary blower speed is selected on the auxiliary HVAC control module, the auxiliary blower motor switch must be in the R position. Voltage is delivered from the fuse block to the auxiliary blower motor on the ignition 3 voltage circuit. The auxiliary blower motor speed control circuit delivers voltage through the auxiliary blower motor relay and through the auxiliary medium 1/2 blower motor control circuit. Voltage is reduced by an in-line resistor in the auxiliary blower motor resistor assembly to achieve the desired blower speed. Ground is provided by the auxiliary blower motor medium speed control circuit, the auxiliary HVAC control module, the auxiliary blower motor switch supply voltage circuit and back into the auxiliary HVAC control module. When the ignition switch is in the ON position, an internal relay inside the auxiliary HVAC control module closes. The relay receives power from the ignition 3 voltage circuit. The ground circuit continues through the closed relay contacts, through the auxiliary blower motor control circuit and auxiliary blower motor switch to the ground circuit. Auxiliary HVAC systems with the premium controls are electronically controlled, there is no internal relay.