Air Speed - Front Control
The blower motor forces outside air into the vehicle's interior. The vehicle operator determines the blower motor's speed when the driver places the blower switch in one of the following positions:^ Low
^ Medium 1
^ Medium 2
^ Medium 3
^ High
The blower motor will operate in any switch position other than OFF, as long as the ignition switch is in the RUN position. When the ignition switch is ON, power from the fuse block is delivered to the blower motor switch through the ignition 3 voltage circuit. The blower motor and mode switches are located within the HVAC control module.
Power is provided to the blower motor from the fuse block. Depending upon selected blower speeds, voltage is either supplied directly to the blower motor or voltage is varied by a series of in-line resistors. Power and ground are provided to the HVAC control module by the ignition 3 voltage and ground circuit.
Low Blower Speed
When the Low blower speed is selected, the HVAC control module applies voltage to the blower motor resistor assembly through the low blower motor control circuit. Voltage is divided between 4 series resistors in the blower motor resistor assembly, the blower motor relay and the blower motor to achieve the desired blower speed. The blower motor is included in the series circuit by the blower motor supply voltage and ground circuits. The ground circuit provides a ground path for the blower motor.
Medium Blower Speeds
When the Medium 1 blower speed is selected, the HVAC control module applies voltage to the blower motor resistor assembly through the medium 1 blower motor control circuit. Voltage is divided between 3 series resistors in the blower motor resistor assembly, the blower motor relay and the blower motor to achieve the desired blower speed. The blower motor is included in the series circuit by the blower motor supply voltage and ground circuits. The ground circuit provides a ground path for the blower motor. When the Medium 2 blower speed is selected, the HVAC control module applies voltage to the blower motor resistor assembly through the medium 2 blower motor control circuit. Voltage is divided between 2 series resistors in the blower motor resistor assembly, the blower motor relay and the blower motor to achieve the desired blower speed. The blower motor is included in the series circuit by the blower motor supply voltage and ground circuits. The ground circuit provides a ground path for the blower motor.
When the Medium 3 blower speed is selected, the HVAC control module applies voltage to the blower motor resistor assembly through the medium 3 blower motor control circuit. Voltage is divided between a series resistor in the blower motor resistor assembly, the blower motor relay and the blower motor to achieve the desired blower speed. The blower motor is included in the series circuit by the blower motor supply voltage and ground circuits. The ground circuit provides a ground path for the blower motor.
High Blower Speed
When the High blower speed is selected, the HVAC control module applies voltage to the blower motor relay through the high blower motor control circuit. When the load side of the relay is energized, the blower motor is connected directly to battery voltage through battery positive voltage circuit. The ground circuit provides a ground path for the blower motor.
Off Mode
When the Off position is selected, the HVAC control module applies voltage to the blower motor switch off input within the HVAC control module through the off blower motor control circuit. Fresh air will still be brought in from the outside.
Recirculation Mode
Recirculation is only available in MAX. When MAX mode is selected, vacuum is applied to the recirculation actuator. The force of the vacuum overcomes the spring pressure of the spring inside the actuator. This moves the actuator, which is linked to the recirculation door, into recirculation mode. This brings air from inside the vehicle instead of fresh air from the outside.