Description

HEATING AND AIR CONDITIONING SYSTEMS

A manual temperature control (MTC) single zone type heating-A/C system or a fully adjustable automatic temperature control (ATC) dual zone type heating-A/C system is available on this vehicle.

To maintain the performance level of the heating, ventilation and air conditioning (HVAC) system, the engine cooling system must be properly maintained. The use of a bug screen is not recommended. Any obstructions in front of the radiator or A/C condenser will reduce the performance of the A/C and engine cooling systems.

The engine cooling system includes the radiator, thermostat, radiator hoses and the engine coolant pump. Refer to Cooling before opening or attempting any service to the engine cooling system.





NOTE: LHD model shown. RHD model similar.

All vehicles are equipped with a common heater, ventilation and air conditioning (HVAC) housing (1). The heating-A/C system combines A/C, heating, and ventilating capabilities in a single HVAC housing mounted within the passenger compartment beneath the instrument panel. The HVAC housing includes:

- Recirculation-air door and actuator (2)
- Blend-air door(s) and actuator(s) (3)
- Blower motor (4)
- Blower motor resistor (MTC) or blower motor power module (ATC) (5)
- Evaporator temperature sensor (6)
- Mode-air doors and actuator (7)
- Heater core (8)
- A/C evaporator (9)

NOTE: An electric positive temperature coefficient (PTC) heater is used on vehicles when equipped with the 3.0L diesel engine. The PTC heater unit compensates for the lower engine coolant temperatures produced by the diesel engine. The PTC heater unit is mounted in the HVAC air distribution housing, downstream of the heater core.

Based upon the system and selected mode, conditioned air can exit the HVAC housing through one or a combination of the three main housing outlets: defrost, panel or floor. The defrost and panel outlets are located on the top of the HVAC housing and the floor outlets are located on the bottom of the HVAC housing. Once the conditioned air exits the HVAC housing, it is further directed through molded plastic ducts to the outlets within the vehicle interior. These outlets and their locations are as follows:

- Defroster Outlets - Two large defroster outlets are located near the center of the instrument panel top cover, near the base of the windshield.
- Side Window Demister Outlets - There are two side window demister outlets, one is located at each outboard end of the instrument panel top cover, near the belt line at the A-pillars.
- Panel Outlets - There are four panel outlets in the instrument panel, one located near each outboard end of the instrument panel facing the rear of the vehicle and one located on each side of the instrument panel center bezel.
- Floor Outlets - There is one floor outlet located above each side of the floor panel center tunnel near the dash panel. There is also one outlet located under each front seat.
- Console Outlets - There are two console outlets located at the back of the center floor console facing the rear of the vehicle.