air condition INFINITI QX56 2010 Factory Service Manual

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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DIAGNOSIS AND REPAIR WORKFLOWHAC-3
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BASIC INSPECTION
DIAGNOSIS AND REPAIR WORKFLOW
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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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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INSPECTION AND ADJUSTMENTHAC-5
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If NG, listen for sound of air mix door motor operat ion. If OK, go to trouble diagnosis procedure for HAC-108,
"Component Function Check". If air mix door motor appears to be malfunctioning, go to HAC-31, "Air Mix Door
Motor (Driver) Component Function Check".
If OK, continue the check.
CHECKING TEMPERATURE INCREASE
1. Rotate temperature control dial clockwise (drive or passenger) until 32 °C (90° F) is displayed.
2. Check for hot air at appropriate discharge air outlets.
If NG, listen for sound of air mix door motor operat ion. If OK, go to trouble diagnosis procedure for HAC-116,
"Component Function Check". If air mix door motor appears to be malfunctioning, go to HAC-31, "Air Mix Door
Motor (Driver) Component Function Check".
If OK, continue with next check.
CHECK A/C SWITCH
1. Press A/C switch when AUTO switch is ON, or in manual mode.
2. A/C switch indicator will turn ON. • Confirm that the compressor clutch engages (sound or visual inspection).
NOTE:
If current mode setting is DEF or D/F, compre ssor clutch will already be engaged and cannot be turned off.
If NG, go to trouble diagnosis procedure for HAC-68, "
Magnet Clutch Diagnosis Procedure".
If OK, continue with next check.
CHECKING AUTO MODE
1. Press AUTO switch.
2. Display should indicate AUTO.
• If ambient temperature is warm, and selected temperat ure is cool, confirm that the compressor clutch
engages (sound or visual inspection). (Discharge air and blower speed will depend on ambient, in-vehi-
cle, and set temperatures.)
If NG, go to trouble diagnosis procedure for HAC-87, "
A/C Auto Amp Power and Ground Diagnosis Proce-
dure", then if necessary, trouble diagnosis procedure for HAC-68, "Magnet Clutch Diagnosis Procedure".
If all operational checks are OK (symptom cannot be duplicated), go to malfunction Simulation Tests in HAC-
3, "How to Perform Trouble Diagnosis For Quick And Accurate Repair" and perform tests as outlined to simu-
late driving conditions environment. If symptom appears. Refer to HAC-107, "
SymptomMatrixChart", and
perform applicable troubl e diagnosis procedures.
Operational Check (Rear)INFOID:0000000005147670
The purpose of the operational check is to confirm that the system operates properly.
CHECKING REAR BLOWER MOTOR
1. Turn the ignition switch ON.
2. Rotate rear air control (front) blower control dial to low speed.
3. Rotate the blower control dial clockwise and continue checking blower speed until all speeds are checked.
4. Leave blower on maximum speed.
5. Press the REAR CTRL switch from the rear air control (front).
6. Rotate rear air control (rear) blower control dial to low speed.
7. Rotate the blower control dial clockwise and continue checking blower speed until all speeds are checked.
8. Leave blower on maximum speed.
If NG, go to trouble diagnosis procedure for HAC-53, "
Rear Blower Motor Component Function Check".
If OK, continue with next check.
CHECKING REAR DISCHARGE AIR
Conditions : Engine running and at normal operating temperature
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HAC-6
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INSPECTION AND ADJUSTMENT
1. The REAR CTRL indicator must be off. Press each rear air con-
trol (front) mode door switches and confirm the discharge air
comes out relative to the icon on each switch and according to
the air distribution table. Refer to HAC-16, "
Discharge Air Flow
(Rear)".
2. Press the REAR CTRL switch (indicator on) from the rear air control (front).
3. Press each rear air control (rear) mode door switches and con-
firm the discharge air comes out relative to the icon on each
switch and according to the air distribution table. Refer to HAC-
16, "Discharge Air Flow (Rear)".
Air mix door position is checked in the next step.
If NG, go to HAC-31, "
Air Mix Door Motor (Driver) Component Func-
tion Check".
If OK, continue with next check.
CHECKING REAR TEMPERATURE DECREASE
1. Press the REAR CTRL switch (indicator off).
2. Rotate the rear air control (front) temperatur e control dial counterclockwise to maximum cold.
3. Check for cold air at appropriate discharge air outlets.
4. Press the REAR CTRL switch (indicator on) from the rear air control (front).
5. Rotate the rear air control (rear) temperature control dial counterclockwise to maximum cold.
6. Check for cold air at appropriate discharge air outlets.
If NG, listen for sound of air mix door motor operation. If OK, go to trouble diagnosis procedure for HAC-31,
"Air Mix Door Motor (Driver) Component Function Check". If air mix door motor appears to be malfunctioning,
go to HAC-59, "
Air Mix Door Motor (Rear) Diagnosis Procedure".
If OK, continue with next check.
CHECKING REAR TEMPERATURE INCREASE
1. Press the REAR CTRL switch (indicator off).
2. Rotate the rear air control (front) temperature control dial clockwise to maximum heat.
3. Check for hot air at appropriate discharge air outlets.
4. Press the REAR CTRL switch (indictor on) from the rear air control (front).
5. Rotate the rear air control (rear) temperature control dial clockwise to maximum heat.
6. Check for hot air at appropriate discharge air outlets.
If NG, listen for sound of air mix door motor operation. If OK, go to trouble diagnosis procedure for HAC-31,
"Air Mix Door Motor (Driver) Component Function Check". If air mix door motor appears to be malfunctioning,
go to HAC-59, "
Air Mix Door Motor (Rear) Diagnosis Procedure".
If NG, go to trouble diagnosis procedure for HAC-116, "
Component Function Check".
If all operational checks are OK (symptom cannot be duplicated), go to HAC-3, "
How to Perform Trouble Diag-
nosis For Quick And Accurate Repair" and perform tests as outlined. If symptom appears, refer to HAC-107,
"SymptomMatrixChart" and perform applicable trouble diagnosis procedures.
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FUNCTION INFORMATIONHAC-7
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FUNCTION DIAGNOSIS
FUNCTION INFORMATION
Component Part LocationINFOID:0000000005147671
ENGINE COMPARTMENT
AWIIA1132GB
1. Water valve F68 2. Refrigerant pressure sensor E48 3. Ambient sensor E1
4. A/C compressor F3
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HAC-8
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FUNCTION INFORMATION
PASSENGER COMPARTMENT
1. A/C auto amp. M49, M50
2. In-vehicle sensor M323. Intake sensor M146
4. Intake door motor M58 5. Variable blower control (front)
M122 6. Air mix door motor (passenger) M143
7. Mode door motor (front) M142 8. Defroster door motor M144 9. Air mix door motor (driver) M147
10. Optical sensor M302 ⇐:Front
AWIIA0567ZZ
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FUNCTION INFORMATIONHAC-9
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REAR PASSENGER COMPARTMENT
Symptom TableINFOID:0000000005147672
1. Rear blower control (rear) 2. Rear mode switch (rear)3. Rear temperature control (rear)
4. Rear blower motor B134 5. Variable blower control (rear) B133 6. Air mix door motor (rear) B155
7. Mode door motor (rear) B156 ⇐: Front
AWIIA0080ZZ
Symptom Reference Page
A/C system does not come on. Go to Trouble Diagnosis Procedure for A/C System. HAC-86
A/C system display is malfunctioning. Go to Navigation System. AV- 6 9
A/C system cannot be controlled.Go to Self-diagnosis Function. HAC-23
Air outlet does not change.
Go to Trouble Diagnosis Procedure for Mode Door Motor. HAC-26
Mode door motor is malfunctioning.
Discharge air temperature does not change.
Go to Trouble Diagnosis Procedure for Air Mix Door Motor. HAC-31
Air mix door motor is malfunctioning.
Intake door does not change.
Go to Trouble Diagnosis Procedure for Intake Door Motor. HAC-40
Intake door motor is malfunctioning.
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HAC-10
< FUNCTION DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
FUNCTION INFORMATION
Defroster door motor is malfunctioning. Go to Trouble Diagnosis Procedure for Defroster Door Motor.
HAC-43
Front blower motor operation is malfunction-
ing.Go to Trouble Diagnosis Procedure for Front Blower Motor.
HAC-48
Rear blower motor operation is malfunction-
ing.Go to Trouble Diagnosis Procedure for Rear Blower Motor.
HAC-53
Rear air discharge outlet does not change. Go to Trouble Diagnosis Procedure for Mode Door Motor (rear). HAC-58
Rear air temperature does not change. Go to Trouble Diagnosis Procedure for Air Mix Door Motor (rear).HAC-58
Magnet clutch does not engage.Go to Trouble Diagnosis Procedure for Magnet Clutch. HAC-68
Insufficient coolingGo to Trouble Diagnosis Procedure for Insufficient Cooling. HAC-108
Insufficient heatingGo to Trouble Diagnosis Procedure for Insufficient Heating. HAC-116
NoiseGo to Trouble Diagnosis Procedure for Noise. HAC-118
Self-diagnosis cannot be performed. Go to Trouble Diagnosis Procedure for Self-diagnosis. HAC-86
Memory function does not operate.Go to Trouble Diagnosis Procedure for Memory Function. HAC-120
SymptomReference Page
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REFRIGERATION SYSTEMHAC-11
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REFRIGERATION SYSTEM
Refrigerant CycleINFOID:0000000005197357
REFRIGERANT FLOW
The refrigerant flows in the standard pattern, that is, through the compressor, the condenser with liquid tank,
through the front and rear evaporators, and back to the compressor. The refrigerant evaporation through the
evaporator coils are controlled by front and rear externally equalized expansion valves, located inside the front
and rear evaporator cases.
Refrigerant System ProtectionINFOID:0000000005197358
REFRIGERANT PRESSURE SENSOR
The refrigerant system is protected against excessively hi gh or low pressures by the refrigerant pressure sen-
sor, located on the condenser. If the system pressure rises above or falls below the specifications, the refriger-
ant pressure sensor detects the pressure inside the refrigerant line and sends a voltage signal to the ECM.
The ECM de-energizes the A/C relay to disengage the magnetic compressor clutch when pressure on the high
pressure side detected by refrigerant pressu re sensor is over about 2,746 kPa (28 kg/cm
2, 398 psi), or below
about 120 kPa (1.22 kg/cm
2, 17.4 psi).
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Revision: April 20092010 QX56