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HEATER & COOLING UNIT ASSEMBLYVTL-15
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HEATER & COOLING UNIT ASSEMBLY
ComponentINFOID:0000000001516610
Front A/C System
WJIA1578E
1. High-pressure service valve 2 . Grommet 3. High-pressure pipe
4. Refrigerant pressure sensor 5. Condenser 6. Compressor shaft seal
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VTL-16
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HEATER & COOLING UNIT ASSEMBLY
Rear A/C System
NOTE:
Refer to HA-5, "
Precaution for Refrigerant Connection".
Removal and InstallationINFOID:0000000001516611
FRONT HEATER AND COOLING UNIT ASSEMBLY
Removal
7. High-pressure flexible hose 8. Low-pressure flexible hose 9. Low-pressure service valve
10. Low-pressure pipe 11. Expansion valve (front) 12. Drain hose
AWIIA0134GB
1. Rear heater and cooling unit assembly 2. Rear A/C pipes 3. Rear A/C heater core pipes
4. Rear heater core hose 5. Rear blower motor6. Underfloor rear A/C pipes
7. Underfloor rear heater core pipes A. Bolt torque specification B. Leak checking order (l - r)
C. Tightening torque D. Wrench sizeE. O-ring size
⇐ Front
NOTE: The O-ring size 8 is the high-side and the O-ring size 16 is the low-side.
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HEATER & COOLING UNIT ASSEMBLYVTL-17
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1. Move the two front seats to the rear most position on the seat track.
2. Disconnect the battery negative terminal and battery positive terminal.
3. Discharge the refrigerant from the A/C system. Refer to HA-20, "
HFC-134a (R-134a) Service Procedure".
4. Drain the coolant from the engine cooling system. Refer to CO-11, "
Changing Engine Coolant".
5. Disconnect the front heater hoses from the front heater core.
6. Disconnect the high/low pressure pipes from the front expansion valve.
7. Remove the instrument panel and console panel. Refer to IP-12, "
Removal and Installation".
8. Remove the steering column. Refer to ST-20, "
Removal and Installation".
9. Disconnect the instrument panel wire harness at t he RH and LH in-line connector brackets, and the fuse
block (J/B) electrical connectors. Refer to PG-9, "
Wiring Diagram — Battery Power Supply —".
10. Disconnect the steering member from each side of the vehicle body.
11. Remove the front heater and cooling unit assembly with it attached to the steering member, from the vehi- cle.
CAUTION:
Use care not to damage the seats and interior trim panels when removing the front heater and
cooling unit assembly with it at tached to the steering member.
12. Remove the front heater and cooling uni t assembly from the steering member.
Installation
Installation is in the reverse order of removal.
CAUTION:
• Replace the O-ring of the low-pressure pipe and high-pressure pipe with a new one, and apply com-
pressor oil to it when installing it.
• After charging the refrigerant, check for leaks.
NOTE:
• Fill the engine cooling system with the specified coolant mixture. Refer to CO-11, "
Changing Engine Cool-
ant".
• Recharge the A/C system. Refer to HA-20, "
HFC-134a (R-134a) Service Procedure".
REAR HEATER AND COOLING UNIT ASSEMBLY
Removal
1. Discharge the refrigerant from the A/C system. Refer to HA-20, "HFC-134a (R-134a) Service Procedure".
2. Drain the coolant from the engine cooling system. Refer to CO-11, "
Changing Engine Coolant".
3. Remove the luggage side finisher lower RH. Refer to INT-19, "
Removal and Installation".
4. Disconnect the rear heater core hoses from the rear heater core.
5. Disconnect the rear A/C pipes from the rear expansion valve.
6. Disconnect the following electrical connectors: • Rear blower motor
• Rear variable blower control
• Rear air mix door motor
7. Disconnect the ducts from the rear heater and cooling unit assembly.
8. Remove the rear heater and cooling unit assembly.
Installation
Installation is in the reverse order of removal.
CAUTION:
• Replace the O-ring of the low-pressure pipe and high-pressure pipe with a new one, and apply com- pressor oil to it when installing it.
• After charging the refrigerant, check for leaks.
NOTE:
• Fill the engine cooling system with the specified coolant mixture. Refer to CO-11, "
Changing Engine Cool-
ant".
• Recharge the A/C system. Refer to HA-20, "
HFC-134a (R-134a) Service Procedure".
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VTL-18
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HEATER CORE
HEATER CORE
ComponentINFOID:0000000001516612
Front Heater and Cooling Unit Assembly
AWIIA0086ZZ
1. Heater core cover2. Heater core pipe bracket3. Heater core
4. Upper bracket 5. Upper heater and cooling unit case 6. A/C evaporator
7. Lower heater and cooling unit case 8. Blower motor 9. Variable blower control
Front
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HEATER COREVTL-19
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Rear Heater and Cooling Unit Assembly
Removal and InstallationINFOID:0000000001516613
FRONT HEATER CORE
Removal
1. Remove the front heater and cooling unit assembly. Refer to VTL-16, "Removal and Installation".
2. Remove the four screws and remove the upper bracket.
3. Remove the four screws and remove the heater core cover.
4. Remove the heater core pipe bracket.
AWIIA0087ZZ
1. Front cover 2. Evaporator and heater core case 3. Evaporator
4. Side cover 5. Heater core 6. Blower motor
7. Blower motor case 8. Variable blower control
Front
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VTL-20
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HEATER CORE
5. Remove the heater core.NOTE:
If the in-cabin microfilters are c ontaminated from coolant leaking
from the heater core, replace the in-cabin microfilters with new
ones before installing the new heater core.
Installation
Installation is in the reverse order of removal.
REAR HEATER CORE
Removal
1. Partially drain the engine cooling system. Refer to CO-11, "Changing Engine Coolant".
2. Remove the luggage side finisher lower RH. Refer to INT-19, "
Removal and Installation".
3. Disconnect the rear heater hoses from the heater core.
4. Remove the rear heater core bracket.
5. Remove the heater core.
Installation
Installation is in the reverse order of removal.
LJIA0134E
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DEFROSTER DOOR MOTORVTL-21
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DEFROSTER DOOR MOTOR
Removal and InstallationINFOID:0000000001516614
Defroster Door Motor - Front Heater and Cooling Unit Assembly
REMOVAL
1. Remove the BCM. Refer to BCS-55, "Removal and Installation".
2. Remove the Bose speaker amplifier. Refer to AV-177, "
Removal and Installation".
3. Disconnect the defroster door motor electrical connector.
4. Remove the three screws and remove the defroster door motor.
INSTALLATION
Installation is in the reverse order of removal.
LJIA0139E
1. Front heater and cooling unit assembly 2. Intake door motor 3. Air mix door motor (driver)
4. Variable blower control 5. Air mix door motor (passenger) 6. Mode door motor
7. Defroster door motor
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VTL-22
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INTAKE DOOR MOTOR
INTAKE DOOR MOTOR
Removal and InstallationINFOID:0000000001516615
Intake Door Motor - Front Heater and Cooling Unit Assembly
REMOVAL
1. Remove the front heater and cooling unit assembly. Refer to VTL-16, "Removal and Installation".
2. Remove the steering member from the front heater and cooling unit assembly.
3. Disconnect the intake door motor electrical connector.
4. Remove the three screws and remove the intake door motor.
INSTALLATION
Installation is in the reverse order of removal.
LJIA0139E
1. Front heater and cooling unit assembly 2. Intake door motor 3. Air mix door motor (driver)
4. Variable blower control 5. Air mix door motor (passenger) 6. Mode door motor
7. Defroster door motor
Revision: March 2010 2008 QX56