air condition INFINITI QX56 2009 Factory Service Manual

INSPECTION AND ADJUSTMENTHAC-5
< BASIC INSPECTION > [AUTOMATIC AIR CONDITIONER]
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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-110,
"Component Function Check". If air mix door motor appears to be malfunctioning, go to HAC-32, "Air Mix Door
Motor 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-118,
"Component Function Check". If air mix door motor appears to be malfunctioning, go to HAC-32, "Air Mix Door
Motor 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-73, "
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-90, "
A/C Auto Amp Power and Ground Diagnosis Proce-
dure", then if necessary, trouble diagnosis procedure for HAC-73, "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-109, "
SymptomMatrixChart", and
perform applicable troubl e diagnosis procedures.
Operational Check (Rear)INFOID:0000000003775326
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-57, "
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
< BASIC INSPECTION >[AUTOMATIC AIR CONDITIONER]
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-32, "
Air Mix Door Motor Component Function
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-32,
"Air Mix Door Motor Component Function Check". If air mix door motor appears to be malfunctioning, go to
HAC-63, "
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-32,
"Air Mix Door Motor Component Function Check". If air mix door motor appears to be malfunctioning, go to
HAC-63, "
Air Mix Door Motor (Rear) Diagnosis Procedure".
If NG, go to trouble diagnosis procedure for HAC-118, "
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-109,
"SymptomMatrixChart" and perform applicable trouble diagnosis procedures.
WJIA0541E
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FUNCTION INFORMATIONHAC-7
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FUNCTION DIAGNOSIS
FUNCTION INFORMATION
Component Part LocationINFOID:0000000003775327
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
< FUNCTION DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
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:0000000003775328
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-89
A/C system display is malfunctioning (with
NAVI).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-32
Air mix door motor is malfunctioning.
Intake door does not change.
Go to Trouble Diagnosis Procedure for Intake Door Motor. HAC-42
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-46
Front blower motor operation is malfunction-
ing.Go to Trouble Diagnosis Procedure for Front Blower Motor.
HAC-51
Rear blower motor operation is malfunction-
ing.Go to Trouble Diagnosis Procedure for Rear Blower Motor.
HAC-57
Rear air discharge outlet does not change. Go to Trouble Diagnosis Procedure for Mode Door Motor (rear). HAC-62
Rear air temperature does not change. Go to Trouble Diagnosis Procedure for Air Mix Door Motor (rear).HAC-62
Magnet clutch does not engage.Go to Trouble Diagnosis Procedure for Magnet Clutch. HAC-72
Insufficient coolingGo to Trouble Diagnosis Procedure for Insufficient Cooling. HAC-110
Insufficient heatingGo to Trouble Diagnosis Procedure for Insufficient Heating. HAC-118
NoiseGo to Trouble Diagnosis Procedure for Noise. HAC-120
Self-diagnosis cannot be performed. Go to Trouble Diagnosis Procedure for Self-diagnosis. HAC-89
Memory function does not operate.Go to Trouble Diagnosis Procedure for Memory Function. HAC-122
SymptomReference Page
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REFRIGERATION SYSTEMHAC-11
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REFRIGERATION SYSTEM
Refrigerant CycleINFOID:0000000004040375
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:0000000004040376
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).
PRESSURE RELIEF VALVE
The refrigerant system is also protected by a pressure relief valve, located in the rear head of the compressor.
When the pressure of refrigerant in the system incr eases to an abnormal level [more than 2,990 kPa (30.5 kg/
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HAC-12
< FUNCTION DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
REFRIGERATION SYSTEM
cm2, 433.6 psi)], the release port on the pressure relief valve automatically opens and releases refrigerant into
the atmosphere.
WJIA1342E
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AUTOMATIC AIR CONDITIONER SYSTEMHAC-13
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AUTOMATIC AIR CONDITIONER SYSTEM
Control System DiagramINFOID:0000000003775331
CONTROL SYSTEM
The control system consists of input sensors, switches, the A/C auto amp.(microcomputer) and outputs.
The relationship of these components is shown in the figure below:
Control System DescriptionINFOID:0000000003775332
CONTROL OPERATION
AWIIA0088GB
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HAC-14
< FUNCTION DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
AUTOMATIC AIR CONDITIONER SYSTEM
A/C auto amp.
DISPLAY SCREEN
Displays the operational status of the system.
AUTO SWITCH
• The compressor, intake door, air mix doors, outlet
doors and blower speed are automatically controlled so
that the in-vehicle temperature will reach, and be mainta ined at the set temperature selected by the operator.
• When pressing AUTO switch, air inlet, air outlet, bl ower speed, and discharge air temperature are automati-
cally controlled.
TEMPERATURE CONTROL DIAL (DRIVER)
Increases or decreases the set temperature.
TEMPERATURE CONTROL DIAL (PASSENGER)
Increases or decreases the set temperature.
RECIRCULATION ( ) SWITCH
• When REC switch is ON, REC switch indicator turns ON, and air inlet is set to REC.
• When REC switch is turned OFF, or when compressor is turned from ON to OFF, REC switch is automati-
cally turned OFF. REC mode can be re-entered by pressing REC switch again.
• REC switch is not operated when DEF switch is tur ned ON, at the D/F position, or in floor position.
DEFROSTER ( ) SWITCH
Positions the air outlet doors to the defrost position. Al so positions the intake doors to the outside air position,
and turns A/C compressor ON.
REAR WINDOW DEFOGGER SWITCH
When switch is ON, rear window and door mirrors are defogged.
OFF SWITCH
The compressor and blower are OFF, the intake doors are set to the outside air position, and the air outlet
doors are set to the foot (75% foot and 25% defrost) position.
A/C SWITCH
The compressor is ON or OFF.
(Pressing the A/C switch when the AUTO switch is ON will turn off the A/C switch and compressor.)
MODE SWITCH
Controls the air discharge outlets.
FRONT BLOWER CONTROL SWITCHES
Manually control the blower speed.
AWIIA0081ZZ
Revision: December 20092009 QX56