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REAR A/C UNITHA-49
< REMOVAL AND INSTALLATION >
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5. Pull out heater core (1) from rear A/C unit assembly.
INSTALLATION
Note the following item, and install in the reverse order of removal.
NOTE:
Refer to CO-9, "
Refilling" when filling radiator with engine coolant.
EXPANSION VALVE
EXPANSION VALVE : Removal and InstallationINFOID:0000000006276192
REMOVAL
1. Remove rear A/C unit assembly. Refer to HA-47, "REAR A/C UNIT ASSEMBLY : Removal and Installa-
tion".
2. Disassembly rear A/C unit assembly.
3. Remove mounting bolts, and then disconnect rear exp ansion valve assembly from rear evaporator pipe
assembly and rear cooler pipe assembly.
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".
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HA-50
< SERVICE DATA AND SPECIFICATIONS (SDS)
SERVICE DATA AND SPECIFICATIONS (SDS)
SERVICE DATA AND SPECIFICATIONS (SDS)
SERVICE DATA AND SPECIFICATIONS (SDS)
CompressorINFOID:0000000006276197
LubricantINFOID:0000000006276198
RefrigerantINFOID:0000000006276199
Engine Idling SpeedINFOID:0000000006276200
Refer to EC-538, "Idle Speed".
Belt TensionINFOID:0000000006276201
Refer to EM-20, "TensionAdjustment".
Model VALEO THERMAL SYSTEMS JAPAN make
DSK-17D
Ty p e Fixation displacement swash plate
Displacement
cm
3 (cu in)/rev Maximum 175 (10.7)
Direction of rotation Clockwise (viewed from clutch)
Drive belt Poly V
Disc to pulley clearance
mm (in) Standard 0.3 – 0.6 (0.012 – 0.024)
Name
UV Luminaus Oil Type S (DH-PS)
Capacity
m (Imp fl oz) Total in system 210 (7.1)
Compressor (service part) charging
amount
210 (7.1)
Ty p e
HFC-134a (R-134a)
Capacity
kg (lb) 1.05 (2.32)
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HAC-1
VENTILATION, HEATER & AIR CONDITIONER
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CONTENTS
HEATER & AIR CONDITIONING CONTROL SYSTEM
AUTOMATIC AIR CONDITIONING
PRECAUTION ................ ...............................
5
PRECAUTIONS .............................................. .....5
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ......
5
SYSTEM DESCRIPTION ..............................6
COMPONENT PARTS ................................... .....6
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM ........................................................................ ......
6
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Component Parts Location .............................
6
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Component Description ..................................
7
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM ........................................................................ ......
8
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM : Component Parts Location .............................
9
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM : Component Description ................................
10
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) ...................................................................... ....
10
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) : Component Parts Location ..........................
11
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) : Component Description ...............................
11
Aspirator ..................................................................12
Front Blower Motor ..................................................12
Rear Blower Motor ..................................................13
Refrigerant Pressure Sensor ...................................13
SYSTEM .............................................................14
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM ........................................................................ ....
14
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : System Diagram ...........................................
14
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : System Description .......................................
14
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Air Flow Control ............................................
15
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Air Inlet Control .............................................
16
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Air Outlet Control ..........................................
17
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Compressor Control ......................................
17
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Door Control ..................................................
18
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Temperature Control .....................................
21
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Fail-safe ........................................................
21
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM ........................................................................ ....
22
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM : System Diagram ...........................................
23
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM : System Description .......................................
23
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM : Air Flow Control ............................................
24
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM : Air Outlet Control ..........................................
25
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM : Door Control ..................................................
26
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM : Temperature Control .....................................
27
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) ....................................................................... ....
27
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) : System Diagram ..........................................
28
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) : System Description ......................................
28
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HAC-2
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) : Automatic Intake Control (Exhaust Gas /
Outside Odor Detecting Mechanism) .....................
28
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) : Plasmacluster Control .................................
29
OPERATION ......................................................30
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM ........................................................................ ...
30
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Switch Name and Function ....................... ...
30
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM ........................................................................ ...
35
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM : Switch Name and Function ....................... ...
35
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) ....................................................................... ...
37
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) : Switch Name and Function .........................
37
DIAGNOSIS SYSTEM (HVAC) ..........................39
Description ........................................................... ...39
CONSULT-III Function ...........................................39
ECU DIAGNOSIS INFORMATION ..............42
A/C AUTO AMP. ............................................. ...42
Reference Value .................................................. ...42
Fail-safe ..................................................................45
DTC Index ..............................................................45
ECM, IPDM E/R .................................................47
List of ECU Reference ......................................... ...47
WIRING DIAGRAM .....................................48
AUTOMATIC AIR CONDITIONING SYSTEM ...48
Wiring Diagram .................................................... ...48
BASIC INSPECTION ...................................60
DIAGNOSIS AND REPAIR WORK FLOW ..... ...60
Work Flow ............................................................ ...60
OPERATION INSPECTION ............................ ...62
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM ........................................................................ ...
62
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Work Procedure ........................................ ...
62
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM ........................................................................ ...
64
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM : Work Procedure ........................................ ...
64
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) ....................................................................... ...
66
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) : Work Procedure ..........................................
66
SYSTEM SETTING ............................................68
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM ........................................................................ ...
68
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Temperature Setting Trimmer (Front) ..........
68
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Foot Position Setting Trimmer ......................
68
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Inlet Port Memory Function (FRE) ................
69
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Inlet Port Memory Function (REC) ...............
69
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM ........................................................................ ...
69
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM : Temperature Setting Trimmer (Rear) ...........
69
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) ....................................................................... ...
70
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) : Exhaust Gas / Outside Odor Detecting
Sensor Sensitivity Adjustment Function ..................
70
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) : Auto Intake Switch Interlocking Movement
Change Function .....................................................
70
DTC/CIRCUIT DIAGNOSIS ........................72
U1000 CAN COMM CIRCUIT ......................... ...72
Description ........................................................... ...72
DTC Logic ...............................................................72
Diagnosis Procedure ...............................................72
U1010 CONTROL UNIT (CAN) .........................73
Description ........................................................... ...73
DTC Logic ...............................................................73
Diagnosis Procedure ...............................................73
B2578, B2579 FRONT IN-VEHICLE SENSOR ...74
DTC Logic ............................................................ ...74
Diagnosis Procedure ...............................................74
Component Inspection ............................................75
B257B, B257C AMBIENT SENSOR .................77
DTC Logic ............................................................ ...77
Diagnosis Procedure ...............................................77
Component Inspection ............................................78
B2581, B2582 INTAKE SENSOR .....................80
DTC Logic ............................................................ ...80
Diagnosis Procedure ...............................................80
Component Inspection ............................................81
B262A, B262B, B2657, B2658 EXHAUST
GAS/OUTSIDE ODOR DETECTING SENSOR
...
83
DTC Logic ............................................................ ...83
Diagnosis Procedure ...............................................83
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HAC-3
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B2630, B2631 SUNLOAD SENSOR (DRIVER
SIDE) .............................................................. ....
86
DTC Logic ........................................................... ....86
Diagnosis Procedure ...............................................86
Component Inspection ............................................87
B2632, B2633 FRONT AIR MIX DOOR MO-
TOR (DRIVER SIDE) ..........................................
89
DTC Logic ........................................................... ....89
Diagnosis Procedure ...............................................89
B2634, B2635 FRONT AIR MIX DOOR MO-
TOR (PASSENGER SIDE) .................................
91
DTC Logic ........................................................... ....91
Diagnosis Procedure ...............................................91
B2636, B2637, B2638, B2639, B2654, B2655
FRONT MODE DOOR MOTOR ..........................
93
DTC Logic ........................................................... ....93
Diagnosis Procedure ...............................................93
B263D, B263E, B263F INTAKE DOOR MO-
TOR ....................................................................
95
DTC Logic ........................................................... ....95
Diagnosis Procedure ...............................................95
B2661, B2662, B2663 UPPER VENTILATOR
DOOR MOTOR ...................................................
97
DTC Logic ........................................................... ....97
Diagnosis Procedure ...............................................97
B2664, B2665 REAR AIR MIX DOOR MOTOR
....
99
DTC Logic ........................................................... ....99
Diagnosis Procedure ...............................................99
B2666, B2669, B266A REAR MODE DOOR
MOTOR .............................................................
101
DTC Logic ........................................................... ..101
Diagnosis Procedure .............................................101
B2667, B2668 SUNLOAD SENSOR (PAS-
SENGER SIDE) ................................................
103
DTC Logic ........................................................... ..103
Diagnosis Procedure .............................................103
Component Inspection ..........................................104
B266B, B266C REAR IN-VEHICLE SENSOR ..106
DTC Logic ........................................................... ..106
Diagnosis Procedure .............................................106
Component Inspection ..........................................107
B27B0 A/C AUTO AMP. ..................................109
DTC Logic ........................................................... ..109
Diagnosis Procedure .............................................109
POWER SUPPLY AND GROUND CIRCUIT ....110
A/C AUTO AMP. .................................................... ..110
A/C AUTO AMP. : Diagnosis Procedure ...............110
FRONT AIR MIX DOOR MOTOR (DRIVER SIDE) ..110
FRONT AIR MIX DOOR MOTOR (DRIVER SIDE)
: Diagnosis Procedure ......................................... ..
110
FRONT AIR MIX DOOR MOTOR (PASSENGER
SIDE) ...................................................................... ..
111
FRONT AIR MIX DOOR MOTOR (PASSENGER
SIDE) : Diagnosis Procedure .................................
111
FRONT MODE DOOR MOTOR ............................. ..112
FRONT MODE DOOR MOTOR : Diagnosis Pro-
cedure ....................................................................
112
INTAKE DOOR MOTOR ........................................ ..113
INTAKE DOOR MOTOR : Diagnosis Procedure ...113
REAR AIR MIX DOOR MOTOR ............................. ..114
REAR AIR MIX DOOR MOTOR : Diagnosis Pro-
cedure .................................................................. ..
114
REAR A/C CONTROL ........................................... ..115
REAR A/C CONTROL : Diagnosis Procedure .......115
REAR MODE DOOR MOTOR ............................... ..116
REAR MODE DOOR MOTOR : Diagnosis Proce-
dure .......................................................................
116
UPPER VENTILATOR DOOR MOTOR ...................116
UPPER VENTILATOR DOOR MOTOR : Diagno-
sis Procedure ....................................................... ..
116
DOOR MOTOR ................................................118
Diagnosis Procedure .............................................118
DOOR MOTOR COMMUNICATION CIRCUIT .120
Diagnosis Procedure .............................................120
FRONT BLOWER MOTOR .............................121
Diagnosis Procedure .............................................121
Component Inspection (Front Blower Motor) .........122
Component Inspection (Blower Relay) ..................123
IONIZER ..........................................................124
Component Function Check ..................................124
Diagnosis Procedure .............................................124
MAGNET CLUTCH .........................................126
Component Function Check ..................................126
Diagnosis Procedure .............................................126
REAR A/C CONTROL COMMUNICATION
SIGNAL ...........................................................
127
Diagnosis Procedure .............................................127
REAR A/C SOLENOID VALVE .......................128
Diagnosis Procedure .............................................128
Component Inspection ...........................................129
REAR BLOWER MOTOR ...............................131
Diagnosis Procedure .............................................131
Component Inspection ...........................................132
SYMPTOM DIAGNOSIS ............................133
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HAC-4
FRONT AUTOMATIC AIR CONDITIONING
SYSTEM .......................................................... .
133
Diagnosis Chart By Symptom .............................. ..133
REAR AUTOMATIC AIR CONDITIONING
SYSTEM .......................................................... .
135
Diagnosis Chart By Symptom .............................. ..135
ACCS (ADVANCE CLIMATE CONTROL
SYSTEM) .........................................................
137
Symptom Table ................................................... ..137
INSUFFICIENT COOLING ...............................138
FRONT AIR CONDITIONER .................................. ..138
FRONT AIR CONDITIONER : Description ............138
FRONT AIR CONDITIONER : Diagnosis Proce-
dure .......................................................................
138
REAR AIR CONDITIONER .................................... ..139
REAR AIR CONDITIONER : Description ...............139
REAR AIR CONDITIONER : Diagnosis Procedure
..
139
INSUFFICIENT HEATING .............................. .140
FRONT AIR CONDITIONER .................................. ..140
FRONT AIR CONDITIONER : Description ............140
FRONT AIR CONDITIONER : Diagnosis Proce-
dure .......................................................................
140
REAR AIR CONDITIONER .................................... ..140
REAR AIR CONDITIONER : Description ...............141
REAR AIR CONDITIONER : Diagnosis Procedure
..
141
COMPRESSOR DOSE DOT OPERATE ........ .142
Description ........................................................... ..142
Diagnosis Procedure .............................................142
REMOVAL AND INSTALLATION ..............144
FRONT A/C CONTROL .................................. .144
Removal and Installation ..................................... ..144
REAR A/C CONTROL .....................................145
Removal and Installation ..................................... ..145
A/C AUTO AMP. ..............................................146
Removal and Installation ..................................... ..146
AMBIENT SENSOR ..........................................147
Removal and Installation ...................................... .147
IN-VEHICLE SENSOR ......................................148
FRONT A/C UNIT ASSEMBLY ...............................148
FRONT A/C UNIT ASSEMBLY : Removal and In-
stallation ............................................................... .
148
REAR A/C UNIT ASSEMBLY .................................148
REAR A/C UNIT ASSEMBLY : Removal and In-
stallation ............................................................... .
148
SUNLOAD SENSOR ........................................149
Removal and Installation ...................................... .149
INTAKE SENSOR .............................................150
Exploded View ..................................................... .150
Removal and Installation .......................................150
EXHAUST GAS/OUTSIDE ODOR SENSOR ...151
Removal and Installation ...................................... .151
DOOR MOTOR .................................................152
Exploded View ..................................................... .152
MODE DOOR MOTOR ........................................... .153
MODE DOOR MOTOR : Removal and Installation .153
AIR MIX DOOR MOTOR ........................................ .153
AIR MIX DOOR MOTOR : Removal and Installa-
tion ....................................................................... .
153
INTAKE DOOR MOTOR ........................................ .153
INTAKE DOOR MOTOR : Removal and Installa-
tion ........................................................................
153
UPPER VENTILATOR DOOR MOTOR ..................154
UPPER VENTILATOR DOOR MOTOR : Removal
and Installation ..................................................... .
154
REAR MODE DOOR MOTOR ................................ .154
REAR MODE DOOR MOTOR : Removal and In-
stallation ................................................................
154
REAR AIR MIX DOOR MOTOR ............................. .154
REAR AIR MIX DOOR MOTOR : Removal and In-
stallation ................................................................
154
IONIZER ............................................................155
Exploded View ..................................................... .155
Removal and Installation .......................................155
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![INFINITI QX56 2011 Factory Service Manual
PRECAUTIONSHAC-5
< PRECAUTION > [AUTOMATIC AIR CONDITIONING]
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PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE INFINITI QX56 2011 Factory Service Manual
PRECAUTIONSHAC-5
< PRECAUTION > [AUTOMATIC AIR CONDITIONING]
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PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE](/manual-img/42/57033/w960_57033-3110.png)
PRECAUTIONSHAC-5
< PRECAUTION > [AUTOMATIC AIR CONDITIONING]
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PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000006275847
The Supplemental Restraint System such as “A IR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severi ty of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the “SRS AIR BAG” and “SEAT BELT” of this
Service Manual.
WARNING:
• To avoid rendering the SRS inoper ative, which could increase the risk of personal injury or death in
the event of a collision that would result in air ba g inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintentional act ivation of the system. For removal of Spiral Cable and Air Bag
Module, see the “SRS AIR BAG”.
Do not use electrical test equipm ent on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identi fied by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
When working near the Air Bag Diagnosis Sensor Unit or other Air Bag System sensors with the
ignition ON or engine running, DO NOT use air or electric power tools or strike near the sensor(s)
with a hammer. Heavy vibration could activate the sensor(s) and deploy the air bag(s), possibly
causing serious injury.
When using air or electric power tools or hammers , always switch the ignition OFF, disconnect the
battery, and wait at least 3 minutes before performing any service.
Revision: 2010 May2011 QX56
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HAC-6
< SYSTEM DESCRIPTION >[AUTOMATIC AIR CONDITIONING]
COMPONENT PARTS
SYSTEM DESCRIPTION
COMPONENT PARTS
FRONT AUTOMATIC AIR CONDITIONING SYSTEM
FRONT AUTOMATIC AIR CONDITIONING
SYSTEM : Component Parts Location
INFOID:0000000006275848
1. Preset switch 2. Engine coolant temperature sensor
Refer to EC-16, "
Component Parts
Location". 3. IPDM E/R
Refer to PCS-4, "
Component Parts
Location".
4. ECM Refer to EC-16, "
Component Parts
Location"
5. Refrigerant pressure sensor 6. Ambient sensor
7. Magnet clutch 8. AV control unit Refer to AV- 9 , "
Component Parts Lo-
cation". 9. Combination meter
Refer to MWI-6, "
METER SYSTEM :
Component Parts Location".
10. Sunload sensor 11. Front display 12. Upper ventilator door motor
JMIIA0812ZZ
Revision: 2010 May2011 QX56