Voltage is supplied to the heater and the air conditioning (A/C) controller by HVAC fuse 9. Power to the blower motor is supplied through the mode selector switch when the switch is in one of the following positions:

S215 splits the power source between the blower motor resistor and the blower switch. When the mode selector switch is in one of the powered positions, power will always be present at cavity B of the blower motor resistor.

In the low position, voltage passes through all 3 resistors in the blower motor resistor through the blower motor relay and to the blower motor.

In MEDIUM 1, voltage passes through 2 resistors.

In MEDIUM 2, voltage goes through 1 resistor.

The HIGH position supplies trigger voltage to the blower motor relay. This condition energizes the blower motor relay and supplies full battery voltage to the blower motor through the HVAC fuse in the underhood fuse block. Ground is provided at G117.