2008 INFINITI QX56 display

AIR MIX DOOR MOTORHAC-31
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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Air Mix Door Control Specification
COMPONENT DESCRIPTION
Air Mix Door Motors (front)
The driver (1) and passenger (2) air mix door motors are attached to
the front heater & cooling unit assembly. These motors rotate so that
the air mix door is opened or closed to a position set by the A/C auto
amp. Motor rotation is then conveyed through a shaft and the air mix
door position is then fed back to t
he A/C auto amp. by the PBR built
into the air mix door motors.
Air Mix Door Motor (rear)
The air mix door motor (rear) (1) is attached to the rear heater &
cooling unit assembly. These motors rotate so that the air mix door is
opened or closed to a position set by the front (or rear) air control.
Motor rotation is then conveyed through a shaft and the air mix door
position is then fed back to the A/C auto amp. by the PBR built into
the air mix door motors.
Air Mix Door Motor Component Function CheckINFOID:0000000001679786
INSPECTION FLOW
1.CONFIRM SYMPTOM BY PERFORMING OPERAT IONAL CHECK - TEMPERATURE INCREASE
1. Turn the temperature control dial (driver) clockwise until 32 °C (90 °F) is displayed.
2. Check for hot air at discharge air outlets.
>> GO TO 2.
2.CONFIRM SYMPTOM BY PERFORMING OPERAT IONAL CHECK - TEMPERATURE DECREASE
1. Turn the temperature control dial (driver) counterclockwise until 18° C (60°F) is displayed.
2. Check for cold air at discharge air outlets.
Can a symptom be duplicated?
YES >> GO TO 4.
NO >> GO TO 3.
3.PERFORM COMPLETE OPERATIONAL CHECK
AWIIA0107GB
AWIIA0109ZZ
AWIIA0111ZZ
Revision: March 2010 2008 QX56

DEFROSTER DOOR MOTOR CIRCUITHAC-45
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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Defroster Door Motor Co mponent Function CheckINFOID:0000000001679793
INSPECTION FLOW
1.CONFIRM SYMPTOM BY PERFORMING O PERATIONAL CHECK - DEFROSTER DOOR
1. Press the mode switch and select vent ( ).
2. Press the defrost switch ( ). Defroster indicator should illuminate (on display).
3. Listen for defroster door position change (blower sound should change slightly).
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.CHECK DEFROSTER DOOR MOTOR
Perform diagnostic procedure for defroster door motor. Refer to HAC-45, "
Defroster Door Motor Component
Function Check".
Is the inspection result normal?
YES >> GO TO 5.
NO >> Repair PBR circuit or replace defroster door motor. Refer to VTL-21, "
Removal and Installation".
5.CHECK DEFROSTER DOOR OPERATION
Check and verify defroster door mechanism for smooth operation.
Is the inspection result normal?
YES >> Replace defroster door motor. Refer to VTL-21, "Removal and Installation".
NO >> Repair defroster door mechanism.
Defroster Door Motor Diagnosis ProcedureINFOID:0000000001679794
SYMPTOM:
• Defroster door does not change.
• Defroster door motor does not operate normally.
DIAGNOSTIC PROCEDURE FOR DEFROSTER DOOR MOTOR
1.CHECK A/C AUTO AMP. FOR POWER AND GROUND
1. Turn ignition switch ON.
2. Press the defroster switch ( ).
3. Check voltage between A/C auto amp. harness connector M49 terminal 24 and terminal 23 and press the defroster switch ( )
again.
Connector Te r m i n a l s
Condition Voltage
(Approx.)
(+) (-)
A/C auto amp.: M49 24 23 Press de-
froster switch Battery
voltage
AWIIA0152ZZ
Revision: March 2010 2008 QX56

MAGNET CLUTCHHAC-71
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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MAGNET CLUTCH
System DescriptionINFOID:0000000001679808
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 OFF as determined by a signal detected by the intake sen-
sor and the ambient sensor.
When intake air temperature is higher than the preset value, 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 Componen t Function CheckINFOID:0000000001679809
INSPECTION FLOW
1.CONFIRM SYMPTOM BY PERFORMING O PERATIONAL 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 ambient, 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-22, "
A/C Auto Amp. Self-Diagnosis".
Are any self-diagnosis codes present?
YES >> Refer to HAC-23, "A/C System Self-Diagnosis Code Chart".
NO >> GO TO 5.
5.CHECK AMBIENT SENSOR
Check and verify ambient s ensor circuit. Refer to HAC-78, "
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: March 2010 2008 QX56

IN-VEHICLE SENSORHAC-81
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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IN-VEHICLE SENSOR
Component DescriptionINFOID:0000000001679816
COMPONENT DESCRIPTION
In-vehicle Sensor
The in-vehicle sensor (1) is located on the lower instrument panel
LH. It converts variations in temperature of passenger compartment
air (drawn in through the integrated fan) into a resistance value. It is
then input into the A/C auto amp.
In-Vehicle Sensor Diagnosis ProcedureINFOID:0000000001679817
DIAGNOSTIC PROCEDURE FOR IN-VEHICLE SENSOR
SYMPTOM: In-vehicle sensor circui t is open or shorted. Using the
CONSULT-III, DTC B2578 or B2579 is displayed. Without a CON-
SULT-III, code 30, 31, 44 or 46 is indicated on A/C auto amp. as a
result of conducting self-diagnosis.
1.CHECK IN-VEHICLE SENSOR CIRCUIT
Is self-diagnosis DTC B2578 or B2579 (with CONSULT-III) or code 30, 31 44 or 46 (without CONSULT-III)
present?
YES or NO?
YES >> GO TO 6.
NO >> GO TO 2.
2.CHECK VOLTAGE BETWEEN IN-VEHICLE SENSOR AND GROUND
AWIIA0164ZZ
AWIIA0165ZZ
AWIIA0166GB
Revision: March 2010 2008 QX56

HAC-84
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
OPTICAL SENSOR
OPTICAL SENSOR
Component DescriptionINFOID:0000000001679819
COMPONENT DESCRIPTION
The optical sensor (1) is located in
the center of the defroster grille. It
detects sunload entering through windshield by means of a photo
diode. The sensor converts the sunload into a current value which is
then input into the A/C auto amp.
OPTICAL INPUT PROCESS
The A/C auto amp. includes a processing circuit which averages the variations in detected sunload over a
period of time. This prevents adjustments in the ATC system operation due to small or quick variations in
detected sunload.
For example, consider driving along a road bordered by an occasional group of large trees. The sunload
detected by the optical sensor will va ry whenever the trees obstruct the sunlight. The processing circuit aver-
ages the detected sunload over a period of time, so that the (insignificant) effect of the trees momentarily
obstructing the sunlight does not cause any change in the ATC system operation. On the other hand, shortly
after entering a long tunnel, the system will recognize the change in sunload, and the system will react accord-
ingly.
Optical Sensor Diagnosis ProcedureINFOID:0000000001679820
DIAGNOSTIC PROCEDURE FOR OPTICAL SENSOR
SYMPTOM: Optical sensor circuit is open or shorted. Using the
CONSULT-III, DTC B257F or B2580 is displayed. Without a CON-
SULT-III, code 50 or 52 is indicated on A/C auto amp. as a result of
conducting self-diagnosis.
1.CHECK CIRCUIT CONTINUITY BETWEEN OPTICAL SENSOR AND A/C AUTO AMP.
1. Turn ignition switch OFF.
2. Disconnect A/C auto amp. connector and optical sensor connec- tor.
3. Check continuity between optical sensor harness connector M302 (B) terminals 1 and 2 and A/C auto amp. harness connec-
tor M50 (C) terminal 42 and M49 (A) terminal 1.
4. Check continuity between optical sensor harness connector M302 (B) terminal 1 and 2 and ground.
AWIIA0169ZZ
AWIIA0205GB
1 - 1 : Continuity should exist.
2 - 42 : Continuity should exist.
AWIIA0206ZZ
Revision: March 2010 2008 QX56

HAC-86
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
INTAKE SENSOR
INTAKE SENSOR
System DescriptionINFOID:0000000001679821
COMPONENT DESCRIPTION
Intake Sensor
The intake sensor is located on t
he heater & cooling unit assembly. It
converts temperature of air after if passes through the evaporator
into a resistance value which is then input to the A/C auto amp.
Intake Sensor Diagnosis ProcedureINFOID:0000000001679822
DIAGNOSTIC PROCEDURE FOR INTAKE SENSOR
SYMPTOM: Intake sensor circuit is open or shorted. Using the CON-
SULT-III, DTC B2581 or B2582 is displayed. Without a CONSULT-III,
code 56 or 57 is indicated on A/C auto amp. as a result of conducting
self-diagnosis.
1.CHECK VOLTAGE BETWEEN IN TAKE SENSOR AND GROUND
1. Disconnect intake sensor connector.
2. Turn ignition switch ON.
3. Check voltage between intake sensor harness connector M146 terminal 2 and ground.
Is the inspection result normal?
YES >> GO TO 2.
NO >> GO TO 4.
2.CHECK CIRCUIT CONTINUITY BETWEEN INTAKE SENSOR AND A/C AUTO AMP.
1. Turn ignition switch OFF.
2. Disconnect A/C auto amp. connector.
3. Check continuity between intake sensor harness connector M146 (B) terminal 1 and A/C auto amp. harness connector M49
(A) terminal 26.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair harness or connector.
WJIA0571E
AWIIA0208GB
2 - Ground : Approx. 5V
WJIA1375E
1 - 26: Continuity should exist.
AWIIA0209ZZ
Revision: March 2010 2008 QX56

HAC-88
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
POWER SUPPLY AND GROUND
CIRCUIT FOR CONTROLLER
POWER SUPPLY AND GROUND CIRCUIT FOR CONTROLLER
Component DescriptionINFOID:0000000001679824
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 built 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. Component Function CheckINFOID:0000000001679825
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 am bient, 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: March 2010 2008 QX56

HAC-108
< SYMPTOM DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
AIR CONDITIONER CONTROL
SYMPTOM DIAGNOSIS
AIR CONDITIONER CONTROL
Symptom Matrix ChartINFOID:0000000001679829
SYMPTOM TABLE
Symptom
Reference Page
A/C system does not come on. Go to Trouble Diagnosis Procedure for A/C System. HAC-88
A/C system display is malfunctioning. Go to Navigation System. AV- 6 4
A/C system cannot be controlled.Go to Self-diagnosis Function. HAC-22
Air outlet does not change.
Go to Trouble Diagnosis Procedure for Mode Door Motor. HAC-25
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-41
Intake door motor is malfunctioning.
Defroster door motor is malfunctioning. Go to Trouble Diagnosis Procedure for Defroster Door Motor. HAC-45
Front blower motor operation is malfunction-
ing.Go to Trouble Diagnosis Procedure for Front Blower Motor.
HAC-50
Rear blower motor operation is malfunction-
ing.Go to Trouble Diagnosis Procedure for Rear Blower Motor.
HAC-56
Rear discharge air temperature and/or air
outlet does not change.Go to Trouble Diagnosis Procedure for Rear Air Control circuit.
HAC-61
Magnet clutch does not engage.Go to Trouble Diagnosis Procedure for Magnet Clutch. HAC-71
Insufficient coolingGo to Trouble Diagnosis Procedure for Insufficient Cooling. HAC-109
Insufficient heatingGo to Trouble Diagnosis Procedure for Insufficient Heating. HAC-117
NoiseGo to Trouble Diagnosis Procedure for Noise. HAC-119
Self-diagnosis cannot be performed. Go to Trouble Diagnosis Procedure for Self-diagnosis. HAC-88
Memory function does not operate.Go to Trouble Diagnosis Procedure for Memory Function. HAC-121
Revision: March 2010 2008 QX56