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 38 in the underhood
bussed electrical center (UBEC). Ground is provided at G117.