2011 INFINITI QX56 heater

ENGINE ASSEMBLYEM-101
< UNIT REMOVAL AND INSTALLATION >
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5. Remove A/T assembly. Refer to
TM-205, "2WD : Exploded View" (2WD models) or TM-208, "4WD :
Exploded View" (4WD models).
6. Remove steering gear assembly. Refer to ST-41, "
Exploded View".
7. Remove front final drive assembly. Refer to DLN-162, "
Exploded View".
8. Remove exhaust manifold. Refer to EM-40, "
Exploded View".
9. Remove alternator. Refer to CHG-25, "
Exploded View".
Engine Room LH
1. Remove air cleaner and air duct. Refer to EM-27, "Exploded View".
2. Remove A/C compressor. Refer to HA-30, "
Exploded View".
3. Disconnect fuel feed hose and EVAP hose. Refer to EM-43, "
Exploded View".
CAUTION:
Fit plugs onto disconnected hoses to prevent fuel leakage.
Engine Room RH
1. Remove power steering oil pump and reservoir tank. Refer to ST-48, "Exploded View".
2. Disconnect heater hose at heater core side, and fit a plug onto hose end to prevent engine coolant leak-
age.
3. Disconnect ground cable.
4. Disconnect all clips and connectors of the engine harness from vehicle side.
Removal Work
1. Install alternator bracket. Refer to CHG-25, "Exploded View".
 Temporarily tighten mounting bolts.
2. Remove intake manifold. Refer to EM-30, "
Exploded View".
3. Remove starter motor. Refer to STR-17, "
Exploded View".
4. Install engine slingers.
5. Lift using a hoist and secure the engine in position.
6. Remove engine mounting bracket (LH, RH) and engine mounting insulator (LH, RH). Refer to EM-98,
"Exploded View".
7. Remove the engine from the vehi cle, avoid interference with the
vehicle body.
CAUTION:
 Before and during lifting, always check that any har-
nesses are left connected.
 Never damage engine mounti ng insulator and avoid oil/
grease smearing or spills onto engine mounting insulator.
A Engine front slinger (bank 2) B Engine rear slinger C Engine front slinger (bank 1)
Slinger bolts:
: 45.0 N·m (4.6 kg-m, 33 ft-lb)
JPBIA3970ZZ
JPBIA3497ZZ
Revision: 2010 May2011 QX56

CYLINDER BLOCKEM-107
< UNIT DISASSEMBLY AND ASSEMBLY >
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Disassembly and AssemblyINFOID:0000000006289583
DISASSEMBLY
1. Remove the following parts:
 Oil pans (lower and upper): Refer to EM-54, "
Exploded View" and EM-57, "Exploded View".
 Front cover and timing chain: Refer to EM-61, "
Exploded View".
 Cylinder head: Refer to EM-86, "
Exploded View".
2. Remove knock sensor. CAUTION:
Carefully handle knock sensor avoiding shocks.
3. Remove oil filter (for VVEL ladder assembly ) from cylinder block, if necessary. Refer to EM-86, "
Exploded
View".
4. Remove piston and connecting rod assembly as per the following:  Before removing piston and connecting rod assembly, check the connecting rod side clearance. Refer to
EM-115, "
Inspection".
CAUTION:
Be careful not to drop connecting r od bearing, and to scratch the surface.
a. Position crankshaft pin corresponding to connecting rod to be removed onto the bottom dead center.
b. Loosen mounting bolts, and remove connecting rod bearing cap.
c. Using a hammer handle (A) or similar tool, push piston and con- necting rod assembly out to the cylinder head side.
CAUTION:
Be careful not to damage the cylinder wall and crankshaft
pin, resulting from an interf erence of the connecting rod big
end.
5. Remove connecting rod bearings from connecting rod and connecting rod bearing cap.
CAUTION:
 Be careful not to drop connecting rod bearing, and to scratch the surface.
 Identify installation positions, and store them without mixing them up.
6. Remove piston rings from piston.  Before removing piston rings, check the piston ring side clearance. Refer to EM-115, "
Inspection".
10. Main bearing cap sub bolt 11. Main bearing cap bolt 12. Connecting rod cap bolt
13. Connecting rod cap 14. Connecting rod bearing 15. Connecting rod
16. Snap ring 17. Piston pin 18. Piston
19. Oil ring 20. Second ring 21. Top ring
22. Pilot converter 23. Drive plate 24. Reinforcement plate
25. Rear oil seal 26. Rear oil seal retainer 27. O-ring
28. Crankshaft position sensor (POS) 29. Cylinder block heater (for Canada)
A.Comply with the assembly procedure
when tightening. Refer to
EM-107
.B. Chamfered C. Installed on transmission
: Crankshaft side
Refer to GI-4, "
Components" for symbol marks in the figure.
JPBIA2475ZZ
Revision: 2010 May2011 QX56

HA-1
VENTILATION, HEATER & AIR CONDITIONER
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SECTION HA
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CONTENTS
HEATER & AIR CONDITIONING SYSTEM
PRECAUTION ................ ...............................3
PRECAUTIONS .............................................. .....3
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ......
3
Precaution Necessary for Steering Wheel Rota-
tion after Battery Disconnect .....................................
3
Precaution for Procedure without Cowl Top Cover ......4
Precautions For Refrigerant System Service ............4
Service Equipment ....................................................6
PREPARATION ............................................9
PREPARATION .............................................. .....9
Special Service Tool ........................................... ......9
Commercial Service Tool ........................................12
Sealant or/and Lubricant .........................................12
SYSTEM DESCRIPTION .............................13
COMPONENT PARTS ................................... ....13
Component Parts Location .................................. ....13
Component Description ...........................................13
SYSTEM .............................................................14
System Diagram .................................................. ....14
System Description .................................................14
BASIC INSPECTION ...................................16
DIAGNOSIS AND REPAIR WORKFLOW ..... ....16
Work Flow ........................................................... ....16
REFRIGERANT ..................................................18
Description .......................................................... ....18
Leak Test ................................................................18
Recycle Refrigerant .................................................20
Charge Refrigerant ..................................................20
LUBRICANT ................................................... ....22
Description .......................................................... ....22
Inspection ............................................................ ....22
Perform Lubricant Return Operation .......................22
Lubricant Adjusting Procedure for Components
Replacement Except Compressor ...........................
22
Lubricant Adjusting Procedure for Compressor
Replacement ...........................................................
23
PERFORMANCE TEST ....................................25
Inspection ................................................................25
SYMPTOM DIAGNOSIS ..............................27
REFRIGERATION SYSTEM SYMPTOMS ........27
Trouble Diagnosis For Unusual Pressure ............ ....27
Symptom Table .......................................................27
NOISE ................................................................29
Symptom Table .......................................................29
REMOVAL AND INSTALLATION ...............30
COMPRESSOR .................................................30
Exploded View ..................................................... ....30
COMPRESSOR ..........................................................30
COMPRESSOR : Removal and Installation ............30
MAGNET CLUTCH ................................................ ....31
MAGNET CLUTCH : Removal and Installation of
Compressor Clutch ..................................................
31
Inspection ................................................................32
COOLER PIPE AND HOSE ..............................33
Exploded View .........................................................33
HIGH-PRESSURE FLEXIBLE HOSE ........................34
HIGH-PRESSURE FLEXIBLE HOSE : Removal
and Installation .................................................... ....
34
LOW-PRESSURE FLEXIBLE HOSE ..................... ....35
LOW-PRESSURE FLEXIBLE HOSE : Removal
and Installation ........................................................
35
HIGH-PRESSURE PIPE ............................................35
Revision: 2010 May2011 QX56

HA-2
HIGH-PRESSURE PIPE : Removal and Installa-
tion ....................................................................... ...
35
LOW-PRESSURE PIPE ......................................... ...36
LOW-PRESSURE PIPE : Removal and Installa-
tion ..........................................................................
36
REAR COOLER PIPE ............................................ ...37
REAR COOLER PIPE : Removal and Installation ...37
CONDENSER ................................................. ...38
Exploded View ..................................................... ...38
CONDENSER ......................................................... ...38
CONDENSER : Removal and Installation ..............38
LIQUID TANK ......................................................... ...39
LIQUID TANK : Removal and Installation ...............39
REFRIGERANT PRESSURE SENSOR ....................39
REFRIGERANT PRESSURE SENSOR : Remov-
al and Installation ................................................. ...
39
A/C UNIT ASSEMBLY .................................... ...41
Exploded View ..................................................... ...41
HEATER & COOLING UNIT ASSEMBLY ................42
HEATER & COOLING UNIT ASSEMBLY : Re-
moval and Installation .......................................... ...
42
EVAPORATOR ...................................................... ...43
EVAPORATOR : Removal and Installation ............43
HEATER CORE ...................................................... ...44
HEATER CORE : Removal and Installation ...........44
EXPANSION VALVE .............................................. ...44
EXPANSION VALVE : Removal and Installation ....44
REAR A/C UNIT ................................................46
Exploded View ..................................................... ...46
REAR A/C UNIT ASSEMBLY ...................................47
REAR A/C UNIT ASSEMBLY : Removal and In-
stallation ............................................................... ...
47
EVAPORATOR ....................................................... ...48
EVAPORATOR : Removal and Installation .............48
EVAPORATOR PIPE ASSEMBLY ........................ ...48
EVAPORATOR PIPE ASSEMBLY : Removal and
Installation ...............................................................
48
HEATER CORE ...................................................... ...48
HEATER CORE : Removal and Installation ............48
EXPANSION VALVE .............................................. ...49
EXPANSION VALVE : Removal and Installation ....49
SERVICE DATA AND SPECIFICATIONS
(SDS) .......... ................................................
50
SERVICE DATA AND SPECIFICATIONS
(SDS) .............................................................. ...
50
Compressor ......................................................... ...50
Lubricant .................................................................50
Refrigerant ..............................................................50
Engine Idling Speed ................................................50
Belt Tension ............................................................50
Revision: 2010 May2011 QX56

COMPONENT PARTSHA-13
< SYSTEM DESCRIPTION >
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SYSTEM DESCRIPTION
COMPONENT PARTS
Component Parts LocationINFOID:0000000006276144
Component DescriptionINFOID:0000000006276145
JMIIA0920ZZ
1. Condenser 2. Refrigerant pressure sensor 3. Liquid tank
4. Compressor 5. Front evaporator 6. Front expansion valve
7. Rear evaporator 8. Rear expansion valve
A. Built-in heater & cooling unit assem- bly B. Built-in rear coolier unit assembly
Component Description
Evaporator The mist form liquid refrigerant transforms to gas by evaporation by the air conveyed from blower
motor. The air is cooled by the heat by evaporation.
Condenser Cools refrigerant discharged from compressor, and transforms it to liquid refrigerant.
Compressor Intakes, compresses, and discharges refrigerant, to circulate refrigerant inside the refrigerant cycle.
Refrigerant pressure sensor Refer to EC-32, "
Refrigerant Pressure Sensor" .
Liquid tank Eliminates foreign matter in refrigerant, and stores temporarily liquid refrigerant.
Expansion valve Transforms high-pressure liquid refrigerant to mist form low-pressure liquid refrigerant by drawing
function.
Revision: 2010 May2011 QX56

COOLER PIPE AND HOSEHA-33
< REMOVAL AND INSTALLATION >
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COOLER PIPE AND HOSE
Exploded ViewINFOID:0000000006276172
FRONT
JMIIA0623GB
1. A/C unit assembly 2. O-ring 3. High-pressure pipe
4. Condenser 5. High-pressure flexible hose 6. Compressor
7. Low-pressure flexible hose 8. Low-pressure pipe 9. Rear cooler and heater pipe assem- bly
A. To rear A/C unit
:Clip
Refer to GI-4, "
Components" for symbols in the figure.
Revision: 2010 May2011 QX56

HA-34
< REMOVAL AND INSTALLATION >
COOLER PIPE AND HOSE
REAR
HIGH-PRESSURE FLEXIBLE HOSE
HIGH-PRESSURE FLEXIBLE HOSE : Removal and InstallationINFOID:0000000006276173
CAUTION:
Perform lubricant return operation before each re frigeration system disassembly. However, if a large
amount of refrigerant or lubrican t is detected, never perform lubricant return operation. Refer to HA-
22, "Perform Lubricant Return Operation".
REMOVAL
1. Use a refrigerant collecting equipment (for HF C-134a) to discharge the refrigerant. Refer to HA-20, "Recy-
cle Refrigerant".
2. Remove air cleaner. Refer to EM-27, "
Removal and Installation".
3. Remove mounting bolt, and then remove high-pressure flexible hose from the vehicle. CAUTION:
Cap or wrap the joint of the A/ C piping, condensor and compressor with suitable material such as
vinyl tape to avoid the entry of air.
INSTALLATION
Note the following items, and install in the reverse order of removal.
CAUTION:
 Replace O-rings with new ones. Then apply compressor oil to them when installing.
JMIIA0625GB
1. Rear A/C unit assembly 2. O-ring 3. Clamp
4. Rear cooler & heater pipe assembly 5. Rear heater bypas hose 6. Rear cooler pipe cover
7. Heater hose 8. Front water outlet tube 9. Gromet
10. Clamp 11. Cap 12. Front heater outlet hose
A. To front cooler sycle B. To front heater core C. To cooling sycle
Refer to GI-4, "
Components" for symbols in the figure.
Revision: 2010 May2011 QX56

COOLER PIPE AND HOSEHA-37
< REMOVAL AND INSTALLATION >
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Cap on wrap the joint of the A/C piping and expan sion valve with suitable material such as vinyl
tape to avoid the entry of air.
10. Remove low-pressure pipe from the vhiecle.
INSTALLATION
Note the following items, and install in the reverse order of removal.
CAUTION:
 Replace O-rings with new ones. Then apply compressor oil to them when installing.
 Check for leakages when recharging refrigerant. Refer to HA-18, "
Leak Test".
REAR COOLER PIPE
REAR COOLER PIPE : Removal and InstallationINFOID:0000000006276177
CAUTION:
Perform lubricant return operati on before each refrigeration system disassembly. However, if a large
amount of refrigerant or lubricant is detected, n ever perform lubricant return operation. Refer to HA-
22, "Perform Lubricant Return Operation".
REMOVAL
1. Use a refrigerant collecting equipment (for HF C-134a) to discharge the refrigerant. Refer to HA-22, "Per-
form Lubricant Return Operation".
2. Separate frame and body. Refer to DLK-251, "
Removal and Installation".
3. Remove mounting bolts, and then disconnect high-pressure pipe and low-pressure pipe from rear cooler & heater pipe assembly.
CAUTION:
Cap or wrap the joint of the A/C piping with suitab le material such as vinyl tape to avoid the entry
air.
4. Remove clamps, and then disconnect rear heater bypas hoses from rear cooler & heater pipe assembly.
5. Remove mounting bolt, and then disconnect rear cooler &. heater pipe assembly from rear expansion
valve.
CAUTION:
Cap or wrap the joint of the A/C piping and rear expansion valve with suitable material such as
vinyl tape to avoid the entry air.
6. Remove clamps, and then disconnect rear cooler & heater pipe assembly from rear heater pipes.
7. Remove mounting nuts, and then remove rear cooler pipe cover.
8. Remove mounting bolts and nuts, and then remove rear cooler & heater pipe assembly from the vehicle.
INSTALLATION
Note the following items, and install in the reverse order of removal.
CAUTION:
 Replace O-rings with new ones. Then apply compressor oil to them when installing.
 Check for leakages when recharging refrigerant. Refer to HA-18, "
Leak Test".
Revision: 2010 May2011 QX56