Auxiliary High Blower Speed

When the High (3) 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 to the auxiliary blower motor relay. Power is also being delivered to the load side of the auxiliary blower motor relay on the ignition 3 voltage circuit. Energizing the relay pulls the internal contact and grounds the blower motor. The load side of the auxiliary blower motor relay is grounded through the auxiliary blower motor supply voltage circuit, the auxiliary blower motor switch and the ground circuit.

When the High (3) 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 to the auxiliary blower motor relay. Power is also being delivered to the load side of the auxiliary blower motor relay on the ignition 3 voltage circuit. Energizing the relay pulls the internal contact and grounds the blower motor. The load side of the auxiliary blower motor relay is grounded through the auxiliary blower motor supply voltage circuit, the auxiliary blower motor switch and the ground circuit.

The load side of the auxiliary blower motor relay is grounded through the auxiliary blower motor supply voltage 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.