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AMBIENT SENSORHA-45
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Removal and InstallationINFOID:0000000005147664
REMOVAL
1. Disconnect the ambient sensor electrical connector. NOTE:
The ambient sensor (1) is located behind the front bumper, in
front of the condenser.
2. Release the ambient sensor clip and then remove the ambient sensor (1).
INSTALLATION
Installation is in the reverse order of removal.
AWIIA0238ZZ
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HA-46
< ON-VEHICLE REPAIR >
REFRIGERANT PRESSURE SENSOR
REFRIGERANT PRESSURE SENSOR
Removal and Installation for Refrigerant Pressure SensorINFOID:0000000005147665
REMOVAL
1. Discharge the refrigerant. Refer to HA-20, "HFC-134a (R-134a) Service Procedure".
2. Disconnect the refrigerant pressure sensor electrical connector and remove the refrigerant pressure sensor from the condenser.
CAUTION:
Be careful not to damage the condenser fins.
INSTALLATION
Installation is in the reverse order of removal.
Refer to HA-29, "
Component".
CAUTION:
• Be careful not to damage the condenser fins.
• Replace the O-ring of the refriger ant pressure sensor with a new one, then apply compressor oil to it
when installing it.
• After charging refrigerant, check for leaks.
LJIA0145E
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EXPANSION VALVEHA-47
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EXPANSION VALVE
Removal and Installation for Front Expansion ValveINFOID:0000000005147666
REMOVAL
1. Discharge the refrigerant. Refer to HA-20, "HFC-134a (R-134a) Service Procedure".
2. Remove the front evaporator. Refer to VTL-19, "
Removal and Installation for Front Evaporator".
3. Remove the cooler grommet.
4. Remove the expansion valve.
INSTALLATION
Installation is in the reverse order of removal.
CAUTION:
• Replace the O-rings on the A/C refrigerant pipes with new ones, th en apply compressor oil to them
when installing them.
• After charging refrigerant, check for leaks.
WJIA0582E
Expansion valve bolts : 4 N·m (0.41 kg-m, 35 in-lb)
A/C refrigerant pipe to expansion valve bolt : Refer to HA-29, "
Component".
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HA-48
< SERVICE DATA AND SPECIFICATIONS (SDS)
SERVICE DATA AND SPECIFICATIONS (SDS)
SERVICE DATA AND SPECIFICATIONS (SDS)
SERVICE DATA AND SPECIFICATIONS (SDS)
Service Data and Specification (SDS)INFOID:0000000005147667
COMPRESSOR
OIL
REFRIGERANT
Make ZEXEL VALEO CLIMATE CONTROL
Model DKS-17D
Ty p e Swash plate
Displacement 175.5 cm
3 (10.7 in3 ) / revolution
Cylinder bore × stroke 30.5 mm (1.20 in) x 24.0 mm (0.94 in)
Direction of rotation Clockwise (viewed from drive end)
Drive belt Poly V
Name NISSAN A/C System Oil Type S
Capacity 290 m (9.8 US fl oz, 10.2 Imp fl oz)
Ty p eHFC 134a (R-134a)
Capacity 1.08 ± 0.05 kg (2.38 ± 0.11 lb)
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HAC-1
VENTILATION, HEATER & AIR CONDITIONER
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HEATER & AIR CONDITIONING CONTROL SYSTEM
AUTOMATIC AIR CONDITIONER
BASIC INSPECTION ....... .............................
3
DIAGNOSIS AND REPAIR WORKFLOW ..... .....3
How to Perform Trouble Diagnosis For Quick And
Accurate Repair ........................................................
3
INSPECTION AND ADJUSTMENT ................ .....4
Operational Check (Front) ................................... ......4
Operational Check (Rear) .........................................5
FUNCTION DIAGNOSIS ...............................7
FUNCTION INFORMATION ........................... .....7
Component Part Location ................................... ......7
Symptom Table .........................................................9
REFRIGERATION SYSTEM ..............................11
Refrigerant Cycle ................................................ ....11
Refrigerant System Protection ................................11
AUTOMATIC AIR CONDITIONER SYSTEM . ....13
Control System Diagram ..................................... ....13
Control System Description .....................................13
Discharge Air Flow (Front) ......................................16
Discharge Air Flow (Rear) .......................................16
Switches And Their Control Function (Front) ..........18
Switches And Their Control Function (Rear) ...........19
DIAGNOSIS SYSTEM (HVAC) ..........................20
CONSULT-III Function (HVAC) ........................... ....20
DIAGNOSIS SYSTEM (BCM) ............................21
CONSULT-III Function (BCM - COMMON ITEM) ....21
CONSULT-III Function (BCM - AIR CONDITION-
ER) ...................................................................... ....
21
SELF-DIAGNOSIS FUNCTION ..........................23
A/C Auto Amp. Self-Diagnosis ................................23
A/C and AV Switch Asse mbly Self-Diagnosis .........23
A/C System Self-Diagnosis Code Chart .............. ....24
COMPONENT DIAGNOSIS .........................25
MODE DOOR MOTOR ......................................25
System Description .............................................. ....25
Mode Door Motor (Front) Component Function
Check ......................................................................
26
Mode Door Motor (Front) Diagnosis Procedure ......26
AIR MIX DOOR MOTOR ...................................30
System Description ..................................................30
Air Mix Door Motor (Driver) Component Function
Check ......................................................................
31
Air Mix Door Motor (Driver) Diagnosis Procedure ....32
Air Mix Door Motor (Passenger) Component
Function Check ........................................................
35
Air Mix Door Motor (Passenger) Diagnosis Proce-
dure .........................................................................
35
INTAKE DOOR MOTOR ...................................39
System Description ..................................................39
Intake Door Motor Component Function Check ......40
Intake Door Motor Diagnosis Procedure .................40
DEFROSTER DOOR MOTOR CIRCUIT ...........42
System Description ..................................................42
Defroster Door Motor Component Function Check
....
43
Defroster Door Motor Diagnosis Procedure ............43
BLOWER MOTOR CONTROL SYSTEM ..........47
System Description ..................................................47
Front Blower Motor Component Function Check ....48
Front Blower Motor Diagnosis Procedure ................48
Front Blower Motor Component Inspection .............52
Rear Blower Motor Description ................................53
Rear Blower Motor Component Function Check .....53
Rear Air Control (Front) Diagnosis Procedure #1 ....54
Rear Air Control (Rear) Diagnosis Procedure #2 ....56
Rear Blower Motor Component Inspection ..............57
REAR AIR CONTROL SYSTEM .......................58
Rear Air Control System Description .......................58
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HAC-2
Rear Air Control Component Function Check ........58
Air Mix Door Motor (Rear) Diagnosis Procedure ....59
Mode Door Motor (Rear) Diagnosis Procedure ......63
MAGNET CLUTCH ............................................68
System Description .............................................. ...68
Magnet Clutch Component Function Check ........ ...68
Magnet Clutch Diagnosis Procedure ................... ...68
WATER VALVE CIRCUIT ..................................73
Description ........................................................... ...73
Water Valve Diagnosis Procedure ..........................73
AMBIENT SENSOR ...........................................75
Component Description ....................................... ...75
Ambient Sensor Diagnosis Procedure ....................75
Ambient Sensor Component Inspection .................76
IN-VEHICLE SENSOR .......................................78
Component Description ....................................... ...78
In-Vehicle Sensor Diagnosis Procedure .................78
In-Vehicle Sensor Component Inspection ..............80
OPTICAL SENSOR ...........................................81
Component Description ..........................................81
Optical Sensor Diagnosis Procedure ......................81
INTAKE SENSOR ..............................................83
System Description .............................................. ...83
Intake Sensor Diagnosis Procedure .......................83
Intake Sensor Component Inspection ................. ...84
POWER SUPPLY AND GROUND CIRCUIT
FOR CONTROLLER ..........................................
86
Component Description ....................................... ...86
A/C Auto Amp. Component Function Check ..........86
A/C Auto Amp Power and Ground Diagnosis Pro-
cedure .................................................................. ...
87
ECU DIAGNOSIS .......................................89
AIR CONDITIONER CONTROL ..................... ...89
A/C Auto Amp. Terminals Reference Values ..........89
Wiring Diagram .................................................... ...91
SYMPTOM DIAGNOSIS ...........................107
AIR CONDITIONER CONTROL ..................... ..107
Symptom Matrix Chart ........................................ .107
INSUFFICIENT COOLING ................................108
Component Function Check ................................ .108
Diagnostic Work Flow ...........................................109
Performance Chart ................................................111
Trouble Diagnoses for Abnormal Pressure ...........112
INSUFFICIENT HEATING ................................116
Component Function Check .................................116
NOISE ...............................................................118
Component Function Check ................................ .118
MEMORY FUNCTION DOES NOT OPERATE ..120
Memory Function Check ...................................... .120
PRECAUTION ...........................................121
PRECAUTIONS .............................................. ..121
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" .............................................................. .
121
Working with HFC-134a (R-134a) ........................ .121
Precaution for Service Equipment ........................122
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How to Perform Trouble Diagnosis F](/manual-img/42/57032/w960_57032-2342.png)
DIAGNOSIS AND REPAIR WORKFLOWHAC-3
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How to Perform Trouble Diagnosis For Quick And Accurate RepairINFOID:0000000005147668
WORK FLOW
1.LISTEN TO CUSTOMER COMPLAINT
Listen to customer complaint. Get detailed information about the conditions and environment when the symp-
tom occurs.
>> GO TO 2
2.CHECK FOR SERVICE BULLETINS
Check for any service bulletins.
>> GO TO 3.
3.VERIFY THE SYMPTOM WITH OPERATIONAL CHECK
Verify the symptom with operational check. Refer to HAC-4, "
Operational Check (Front)".
Can a symptom be duplicated?
YES >> GO TO 4
NO >> GO TO 5
4.GO TO APPROPRIATE TROUBLE DIAGNOSIS
Go to appropriate trouble diagnosis. Refer to HAC-107, "
SymptomMatrixChart".
Can a symptom be duplicated?
>> GO TO 5.
5.PERFORM THE A/C AUTO AMP SELF-DIAGNOSIS
Perform A/C auto amp. self-diagnosis. Refer to HAC-23, "
A/C Auto Amp. Self-Diagnosis".
>> If any diagnostic trouble codes set. Refer to HAC-24, "
A/C System Self-Diagnosis Code Chart".
>> Confirm the repair by perform ing operational check. Refer to HAC-4, "
Operational Check (Front)".
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INSPECTION AND ADJUSTMENT
INSPECTION AND ADJUSTMENT
Operational Check (Front)INFOID:0000000005147669
The purpose of the operational check is to
c INFINITI QX56 2010 Factory Service Manual HAC-4
< BASIC INSPECTION >[AUTOMATIC AIR CONDITIONER]
INSPECTION AND ADJUSTMENT
INSPECTION AND ADJUSTMENT
Operational Check (Front)INFOID:0000000005147669
The purpose of the operational check is to
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HAC-4
< BASIC INSPECTION >[AUTOMATIC AIR CONDITIONER]
INSPECTION AND ADJUSTMENT
INSPECTION AND ADJUSTMENT
Operational Check (Front)INFOID:0000000005147669
The purpose of the operational check is to
confirm that the system operates properly.
CHECKING MEMORY FUNCTION
1. Set the temperature to 32 ° (90 °F).
2. Press the OFF switch.
3. Turn ignition switch OFF.
4. Turn ignition switch ON.
5. Press the AUTO switch.
6. Confirm that the set temperature remains at previous temperature.
7. Press the OFF switch.
If NG, go to trouble diagnosis procedure for HAC-120, "
Memory Function Check".
If OK, continue with next check.
CHECKING BLOWER
1. Press the blower speed control switch (+) once, blower should operate on low speed. The fan display should have one bar lit (on display).
2. Press the blower speed control switch (+) again, and continue checking blower speed and fan display until
all speeds are checked.
3. Leave blower on maximum speed.
If NG, go to trouble diagnosis procedure for HAC-48, "
Front Blower Motor Diagnosis Procedure".
If OK, continue with next check.
CHECKING DISCHARGE AIR
1. Press MODE switch four times and the DEF switch.
2. Each position indicator should change shape (on display).
3. Confirm that discharge air comes out according to the air distribution table. Refer to HAC-16, "
Discharge
Air Flow (Front)".
Mode door position is checked in the next step.
If NG, go to trouble diagnosis procedure for HAC-26, "
Mode Door Motor (Front) Diagnosis Procedure".
If OK, continue the check.
NOTE:
Confirm that the compressor clutch is engaged (sound or visual inspection) and intake door position is at
fresh when the DEF or D/F is selected.
CHECKING RECIRCULATION ( , ONLY)
1. Press recirculation ( ) switch one time. Recirculation indicator should illuminate.
2. Press recirculation ( ) switch one more time. Recirculation indicator should go off.
3. Listen for intake door position change (blower sound should change slightly).
If NG, go to trouble diagnosis procedure for HAC-40, "
Intake Door Motor Diagnosis Procedure".
If OK, continue the check.
NOTE:
Confirm that the compressor clutch is engaged (sound or vis ual inspection) and intake door position is at fresh
when the DEF or D/F is selected. REC ( ) is not allowed in DEF ( ) D/F ( ) or FOOT ( ).
CHECKING TEMPERATURE DECREASE
1. Rotate temperature control dial (drive or passenger) counterclockwise until 18° C (60°F) is displayed.
2. Check for cold air at appropriate discharge air outlets. Conditions : Engine running and at normal operating temperature
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