2009 INFINITI QX56 clutch

HAC-72
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
MAGNET CLUTCH
MAGNET CLUTCH
System DescriptionINFOID:0000000003775369
SYSTEM DESCRIPTION
The A/C auto amp. controls compressor operation
based on ambient and intake temperature and a signal
from ECM.
Low Temperature Protection Control
The A/C auto amp. will turn the compressor ON or O FF as determined by a signal detected by the intake sen-
sor and the ambient sensor.
When intake air temperature is higher than the preset va lue, the compressor turns ON. The compressor turns
OFF when intake air temperature is lower than the pres et value. That preset value is dependent on the ambi-
ent temperature, refer to the following table.
Magnet Clutch Com ponent Function CheckINFOID:0000000003775370
INSPECTION FLOW
1.CONFIRM SYMPTOM BY PERFORMING OP ERATIONAL CHECK - MAGNET CLUTCH
1. Turn ignition switch ON.
2. Press the A/C switch.
3. Press vent switch ( ).
4. Display shows , A/C. Confirm that the compress or clutch engages (sound or visual inspection). (Dis-
charge air and blower speed will depend on ambi ent, in-vehicle and set temperatures.)
Can the symptom be duplicated?
YES >> GO TO 3.
NO >> GO TO 2.
2.CHECK FOR ANY SYMPTOMS
Perform a complete operational check for any symptoms. Refer to HAC-4, "
Operational Check (Front)".
Does another symptom exist?
YES >> Refer to HAC-3, "How to Perform Trouble Diagnosis For Quick And Accurate Repair".
NO >> System OK.
3.CHECK FOR SERVICE BULLETINS
Check for any service bulletins.
>> GO TO 4.
4.PERFORM SELF-DIAGNOSIS
Perform self-diagnosis to check for any codes. Refer to HAC-23, "
A/C Auto Amp. Self-Diagnosis".
Are any self-diagnosis codes present?
YES >> Refer to HAC-24, "A/C System Self-Diagnosis Code Chart".
NO >> GO TO 5.
5.CHECK AMBIENT SENSOR
Check and verify ambient sensor circuit. Refer to HAC-79, "
Ambient Sensor Diagnosis Procedure".
Ambient temperature °C ( °F) Compressor ON intake temperature °C ( °F) Compressor OFF intake temperature °C ( °F)
0 (32) 5.5 (42) 5.0 (41)
10 (50) 5.5 (42) 5.0 (41)
20 (68) 5.5 (42) 5.0 (41)
30 (86) 4.0 (39) 3.5 (38)
40 (104) 3.5 (38) 3.0 (37)
50 (122) 3.5 (38) 3.0 (37)
Revision: December 20092009 QX56

MAGNET CLUTCHHAC-73
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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>> GO TO 6.
6.CHECK INTAKE SENSOR
Check and verify intake sensor circuit. Refer to HAC-87, "
Intake Sensor Diagnosis Procedure".
>> GO TO 7.
7.RECHECK FOR ANY SYMPTOMS
Perform a complete operational check for any symptoms. Refer to HAC-4, "
Operational Check (Front)" .
Does another symptom exist?
YES >> Refer to HAC-3, "How to Perform Trouble Diagnosis For Quick And Accurate Repair" .
NO >> Replace A/C auto amp. Refer to VTL-7, "
Removal and Installation".
Magnet Clutch Diagnosis ProcedureINFOID:0000000003775371
DIAGNOSTIC PROCEDURE FOR MAGNET CLUTCH
SYMPTOM: Magnet clutch does not engage when A/C switch is ON.
1.CHECK INTAKE AND AMBIENT SENSOR CIRCUITS
Check intake and ambient sensors. Refer to HAC-23, "
A/C and AV Switch Assembly Self-Diagnosis".
Is the inspection result normal?
YES >> GO TO 2.
NO >> • Malfunctioning intake sensor. Refer to HAC-87, "
Intake Sensor Diagnosis Procedure".
• Malfunctioning ambient sensor. Refer to HAC-79, "
Ambient Sensor Diagnosis Procedure".
2.PERFORM AUTO ACTIVE TEST
Refer to PCS-14, "
CONSULT - III Function (IPDM E/R)".
Does magnet clutch operate?
YES >> • WITH CONSULT-III GO TO 5.
• WITHOUT CONSULT-III GO TO 6.
AWIIA1070GB
Revision: December 20092009 QX56

HAC-74
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
MAGNET CLUTCH
NO >> Check 10A fuse (No. 42, located in IPDM E/R), and GO TO 3.
3.CHECK CIRCUIT CONTINUITY BETW
EEN IPDM E/R AND COMPRESSOR
1. Turn ignition switch OFF.
2. Disconnect IPDM E/R connector and compressor (magnet clutch) connector.
3. Check continuity between IPDM E/R harness connector E119
terminal 11 and A/C compressor harness connector F3 terminal
1.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair harness or connector.
4.CHECK MAGNET CLUTCH CIRCUIT
Check for operation sound when applying battery voltage direct cur-
rent to terminal.
Is the inspection result normal?
YES >> Replace IPDM E/R. Refer to PCS-34, "Removal and
Installation of IPDM E/R".
NO >> Replace magnet clutch. Refer to HA-32, "
Removal and
Installation for Compressor Clutch".
5.CHECK BCM INPUT (COMPRESSOR ON) SIGNAL
Check compressor ON/OFF signal. Refer to HAC-20, "
CONSULT-III Function (HVAC)".
Is the inspection result normal?
YES >> GO TO 8.
NO >> GO TO 6.
6.CHECK CIRCUIT CONTINUITY BETW EEN BCM AND A/C AUTO AMP.
1. Turn ignition switch OFF.
2. Disconnect BCM connector and A/C auto amp. connector.
3. Check continuity between BCM harness connector M18 (A) ter- minal 27 and A/C auto amp. harness connector M49 (B) terminal
4.
Is the inspection result normal?
YES >> GO TO 7.
NO >> Repair harness or connector.
7.CHECK VOLTAGE FOR A/C AUTO AMP. (A/C COMPRESSOR ON SIGNAL)
11 – 1
: Continuity should exist.
WJIA0560E
SJIA0197E
A/C SW ON: COMP ON SIG ON
A/C SW OFF : COMP ON SIG OFF
27 - 4 Continuity should exist.
AWIIA0199ZZ
Revision: December 20092009 QX56

MAGNET CLUTCHHAC-75
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1. Reconnect BCM connector and A/C auto amp. connector.
2. Turn ignition switch ON.
3. Check voltage between A/C auto amp. harness connector M49 terminal 4 and ground.
Is the inspection result normal?
YES >> GO TO 8.
NO-1 >> If the voltage is approx. 5V when A/C swit ch is ON, replace A/C auto amp. Refer to VTL-7,
"Removal and Installation".
NO-2 >> If the voltage is approx. 0V when A/C switch is OFF, replace BCM. Refer to BCS-56, "
Removal
and Installation".
8.CHECK REFRIGERANT PRESSURE SENSOR
1. Start engine.
2. Check voltage between ECM harness connector F54 terminal 70 and ground.
Is the inspection result normal?
YES >> GO TO 9.
NO >> Refer to EC-416, "
Diagnosis Procedure".
9.CHECK BCM INPUT (FAN ON) SIGNAL
Check FAN ON/OFF signal. Refer to HAC-20, "
CONSULT-III Function (HVAC)".
Is the inspection result normal?
YES >> GO TO 12.
NO >> GO TO 10.
10.CHECK CIRCUIT CONTINUITY BETW EEN BCM AND A/C AUTO AMP.
Te r m i n a l s
Condition Voltage
(+)
(-)
A/C auto
amp. con-
nector Te r m i n a l N o .
M49 4 Ground A/C switch: ON Approx. 0V
A/C switch: OFF Approx. 5V
AWIIA0200ZZ
Te r m i n a l s
ConditionVoltage
(+)
(-)
ECM con-
nector Te r m i n a l N o .
F54 70 Ground A/C switch: ON Approx. 0.36 - 3.88V
LJIA0124E
FRONT BLOWER CONTROL
DIAL ON : FAN ON SIG ON
FRONT BLOWER CONTROL
DIAL OFF : FAN ON SIG OFF
Revision: December 20092009 QX56

HAC-76
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
MAGNET CLUTCH
1. Turn ignition switch OFF.
2. Disconnect BCM connector and A/C auto amp. connector.
3. Check continuity between BCM harness connector M18 (A) ter-
minal 28 and A/C auto amp. harness connector M49 (B) terminal
5.
Is the inspection result normal?
YES >> GO TO 11.
NO >> Repair harness or connector.
11 .CHECK VOLTAGE FOR A/C AUTO AMP. (FAN ON SIGNAL)
1. Reconnect BCM connector and A/C auto amp. connector.
2. Turn ignition switch ON.
3. Check voltage between A/C auto amp. harness connector M49 terminal 5 and ground.
Is the inspection result normal?
YES >> GO TO 12.
NO-1 >> If the voltage is approx. 5V when blower motor is ON, replace A/C auto amp. Refer to VTL-7,
"Removal and Installation".
NO-2 >> If the voltage is approx. 0V when blower motor is OFF, replace BCM. Refer to BCS-56, "
Removal
and Installation".
12.CHECK CAN COMMUNICATION
Check CAN communication. Refer to LAN-4, "
System Description".
•BCM – ECM
• ECM – IPDM E/R
• ECM – A/C auto amp.
Is the inspection result normal?
YES >> Inspection End.
NO >> Repair or replace malfunctioning part(s). 28 - 5
Continuity should exist.
AWIIA0201ZZ
Te r m i n a l s
Condition Voltage
(+)
(-)
A/C auto amp.
connector Te r m i n a l N o .
M49 5GroundA/C switch: ON
Blower motor
operates
Approx. 0V
A/C switch: OFF Approx. 5V
AWIIA0202ZZ
Revision: December 20092009 QX56

POWER SUPPLY AND GROUND CIRCUIT FOR CONTROLLER
HAC-89
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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POWER SUPPLY AND GROUND CIRCUIT FOR CONTROLLER
Component DescriptionINFOID:0000000003775385
COMPONENT DESCRIPTION
A/C auto amp.
The A/C auto amp. has a built-in microcomputer which processes
information sent from various sensors needed for air conditioner
operation. The air mix door motors, mode door motor, intake door
motor, defroster door motor, blower motor and compressor are then
controlled.
The A/C auto amp. is unitized with control mechanisms. When the
various switches and temperature dials are operated, data is input to
the A/C auto amp.
Self-diagnostic functions are also bu ilt into the A/C auto amp. to pro-
vide quick check of malfunctions in the auto air conditioner system.
Potentio Temperature Control (PTC)
There are two PTCs (driver and passenger) built into the A/C auto
amp. They can be set at an interval of 0.5 °C (1.0 °F) in the 18° C
(60 °F) to 32 °C (90° F) temperature range by rotating the temperature
dial. The set temperature is displayed.
A/C Auto Amp. Com ponent Function CheckINFOID:0000000003775386
SYMPTOM: A/C system does not come on.
INSPECTION FLOW
1.CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - AUTO MODE
1. Press AUTO switch.
2. Display should indicate AUTO. Confirm that the compressor clutch engages (sound or visual inspection). (Discharge air and blower speed will depend on ambient, in-vehicle and set temperatures.)
Can a symptom be duplicated?
YES >> GO TO 3.
NO >> GO TO 2.
2.PERFORM COMPLETE OPERATIONAL CHECK
Perform a complete operational check and check for any symptoms. Refer to HAC-4, "
Operational Check
(Front)".
Can a symptom be duplicated?
YES >> Refer to HAC-3, "How to Perform Trouble Diagnosis For Quick And Accurate Repair".
NO >> System OK.
3.CHECK FOR SERVICE BULLETINS
Check for any service bulletins.
>> GO TO 4.
4.CHECK POWER AND GROUND CIRCUIT
AWIIA0573ZZ
AWIIA0211GB
Revision: December 20092009 QX56

AIR CONDITIONER CONTROLHAC-109
< SYMPTOM DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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SYMPTOM DIAGNOSIS
AIR CONDITIONER CONTROL
Symptom Matrix ChartINFOID:0000000003775390
SYMPTOM TABLE
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. 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.
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 discharge air temperature and/or air
outlet does not change.Go to Trouble Diagnosis Procedure for Rear Air Control circuit.
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
Revision: December 20092009 QX56

INSUFFICIENT COOLINGHAC-113
< SYMPTOM DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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Performance ChartINFOID:0000000003775393
Test Condition
Testing must be performed as follows:
*1 VTL-12, "Removal and Installation"*2HAC-51, "Front Blower Motor Com-
ponent Function Check"
*3 HA-32, "Removal and Installation for
Compressor Clutch"
*4EM-13, "Checking Drive Belts"*5HA-31, "Removal and Installation for
Compressor"
AWIIA1000GB
Revision: December 20092009 QX56