CORE-HEATER
DESCRIPTION
NOTE: LHD model shown. RHD model similar.
The heater core (1) is mounted into the HVAC air distribution housing, located behind the instrument panel. The heater core is a heat exchanger made of rows of tubes and fins. The heater core tubes (2) are attached to the HVAC housing by a bracket and screw (3) and to the heater core by a flange and bolt (4).
The heater core can be serviced without removing the air distribution housing from the vehicle.
OPERATION
Engine coolant is circulated through the heater hoses to the heater core at all times. As the coolant flows through the heater core, heat is removed from the engine and is transferred to the heater core tubes and fins. Air directed through the heater core picks up the heat from the heater core fins. The blend-air door(s) allows control of the heater output air temperature by regulating the amount of air flowing through the heater core. The blower motor speed controls the volume of air flowing through the HVAC housing.
The heater core cannot be repaired and must be replaced if found to be restricted, leaking or damaged.
REMOVAL
WARNING: Refer to the applicable warnings and cautions for this system before performing the following operation (refer to 24 - HEATING & AIR CONDITIONING/PLUMBING - WARNING) and (refer to 24 - HEATING & AIR CONDITIONING/PLUMBING - CAUTION). Failure to follow the warnings and cautions could result in possible personal injury or death.
WARNING: Disable the airbag system before attempting any steering wheel, steering column, or instrument panel component diagnosis or service. Disconnect and isolate the negative battery (ground) cable, then wait two minutes for the airbag system capacitor to discharge before performing further diagnosis or service. This is the only sure way to disable the airbag system. Failure to take the proper precautions could result in accidental airbag deployment and possible personal injury or death.
NOTE: Take the proper precautions to protect the front face of the instrument panel from cosmetic damage while performing this procedure.
NOTE: LHD model shown in illustrations. RHD model similar.
1. Drain the engine cooling system (refer to 7 - COOLING - STANDARD PROCEDURE - COOLING SYSTEM DRAIN).
2. Disconnect and isolate the negative battery cable.
3. If required, disconnect the heater hoses from the heater core tubes in the engine compartment.
4. Remove the instrument panel (refer to 23 - BODY/INSTRUMENT PANEL/INSTRUMENT PANEL ASSEMBLY - REMOVAL).
5. Remove the five screws (1) that secure the heater core and tube cover (2) to the HVAC housing (3).
6. Remove the heater core and tube cover from the HVAC housing.
7. If equipped with dual zone heating-A/C, remove the blend door actuator (1) from the passenger side of the HVAC air distribution housing (2) (refer to 24 - HEATING & AIR CONDITIONING/CONTROLS/ACTUATOR-BLEND DOOR - REMOVAL).
8. Remove the screw (3) that secure the heater core tubes (4) and retaining bracket (5) to the HVAC housing (6).
NOTE: Take proper precautions to protect the carpeting from engine coolant. Have absorbent toweling readily available to clean up any spills.
9. Remove the bolt (7) that secures the heater tubes to the heater core (8).
10. Disconnect the heater core tubes from the heater core and remove and discard the O-ring seals.
11. Install plugs in, or tape over the opened heater core ports.
12. Carefully pull the heater core out of the HVAC air distribution housing.
13. If required, remove the heater core tubes from the vehicle.
INSTALLATION
NOTE: LHD model shown in illustrations. RHD model similar.
1. Carefully install the heater core (8) into the passenger side of the HVAC air distribution housing (2).
2. Remove the tape or plugs from the heater core ports.
3. If removed, position the heater core tubes (4) into the vehicle.
4. Lubricate new rubber O-ring seals with clean engine coolant and install them onto the heater core tubes. Use only the specified O-ring as they are made of a special material for the engine cooling system.
5. Connect the heater core tubes to the heater core.
6. Install the bolt (7) that secures the heater core tubes to the heater core. Tighten the bolt securely.
7. Install the screw (3) that secures the heater core tube retaining bracket (5) to the HVAC housing (6). Tighten the screw to 2.2 N·m (20 in. lbs.).
8. If equipped with dual zone heating-A/C, install the blend door actuator (1) onto the passenger side of the HVAC air distribution housing (refer to 24 - HEATING & AIR CONDITIONING/CONTROLS/ACTUATOR-BLEND DOOR - INSTALLATION).
9. Install the heater core and tube cover (2) onto the HVAC housing (3).
10. Install the five screws (1) that secure the heater core and tube cover to the HVAC housing. Tighten the screws to 2.2 N·m (20 in. lbs.).
11. Install the instrument panel (refer to 23 - BODY/INSTRUMENT PANEL/INSTRUMENT PANEL ASSEMBLY - INSTALLATION).
12. If disconnected, connect the heater hoses to the heater core tubes in the engine compartment.
13. Connect the negative battery cable.
14. If the heater core is being replaced, flush the cooling system (refer to 7 - COOLING - STANDARD PROCEDURE - COOLING SYSTEM CLEANING/REVERSE FLUSHING).
15. Refill the engine cooling system (refer to 7 - COOLING - STANDARD PROCEDURE - COOLING SYSTEM REFILL).