Heating and Ventilation

The heating and ventilation system has the following features:

• Controls the temperature and, during A/C operation, reduces the relative humidity of the air inside the vehicle
• Delivers heated or cooled air to maintain the vehicle interior temperature and comfort level
• Cooling or heating can be adjusted to maintain the desired temperature

The heating and ventilation system includes the:

• Blower motor
• Heater core and evaporator core housing
• Heater core

Blower Motor

The blower motor draws air from the air inlet and forces it into the heater core and evaporator core housing where it is mixed and distributed. The blower motor receives battery voltage when the ignition is in the RUN position with the HVAC module in an ON position, and is grounded by the blower motor speed control.

Heater Core and Evaporator Core Housing

The heater core and evaporator core housing directs airflow from the blower motor through the evaporator core and heater core. All airflow from the blower motor passes through the evaporator core. The airflow is then directed through or around the heater core by the temperature blend door(s). After passing through the heater core, the airflow is distributed to the selected outlet by the plenum chamber.

Heater Core

NOTE: The heater core is not individually serviced. It is serviced only with the heater core and evaporator core housing.

The heater core receives a flow of coolant from the engine cooling system through the heater core inlet. A restrictor is installed in the heater core inlet hose on V8 models to eliminate noise. The heater core consists of fins and tubes arranged to extract heat from the engine coolant and transfer it to air passing through the heater core. The engine coolant is then returned to the engine cooling system through the heater core outlet.