CORE-HEATER
DESCRIPTION
The rear heater core (1) is located in the rear HVAC housing, behind the right interior quarter trim panel. The rear heater core is a heat exchanger made of rows of tubes and fins. The heater core tubes (3) are attached to the heater core by metal retaining clamps (2) and rubber O-ring seals
The rear HVAC housing must be removed from the vehicle to service the rear heater core.
OPERATION
Engine coolant is circulated through heater hoses and tubes to the rear heater core at all times. As the coolant flows through the heater core, heat removed from the engine is transferred to the heater core fins and the air directed through the heater core picks up the heat from the fins. The rear blend air door allows control of the rear heater output air temperature by controlling the amount of air flowing through or around the rear heater core. The rear blower motor speed controls the volume of air flowing through the rear heater-A/C housing.
The rear heater core cannot be repaired and must be replaced if found to be inoperative, leaking or damaged.
REMOVAL
1. Remove the rear HVAC housing and place it on a workbench (refer to 24 - HEATING & AIR CONDITIONING/DISTRIBUTION - REAR/HOUSING-HVAC - REMOVAL).
2. Carefully remove the foam seal (1) from the flange (2) located at the bottom of the rear HVAC housing (3). If the seal is deformed or damaged, it must be replaced.
3. Partially bend the inner half of the flange downward and remove the heater core tubes (4) from the flange.
4. Release the two tabs (1) that secure the rear heater core (2) in the rear HVAC housing (3).
5. Carefully pull the rear heater core out of the end of the rear HVAC housing. If the foam seals on the heater core are deformed or damaged, they must be replaced.
6. If required, remove the heater core tubes from the rear heater core and remove and discard the O-ring seals.
INSTALLATION
1. Install the rear heater core (2) into the end of the rear HVAC housing (3). Make sure that the foam seals are properly installed and that the two retaining tabs (1) are fully engaged.
2. If the rear heater core tubes where removed from the heater core, 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. Connect the heater core tubes to the heater core and install two retaining clamps securely.
3. Partially bend the inner half of the flange (2) located at the bottom of the rear HVAC housing (3) downward and install the heater core tubes (4) into the flange.
4. Install the foam seal (1) onto the flange. If the seal is deformed or damaged, it must be replaced.
NOTE: If the heater core is being replaced, flush the cooling system (refer to 7 - COOLING - STANDARD PROCEDURE - COOLING SYSTEM CLEANING/REVERSE FLUSHING).
5. Install the rear HVAC housing (refer to 24 - HEATING & AIR CONDITIONING/DISTRIBUTION - REAR/HOUSING-HVAC - INSTALLATION).