diagram INFINITI QX56 2010 Factory Service Manual

AUTOMATIC AIR CONDITIONER SYSTEMHAC-13
< FUNCTION DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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AUTOMATIC AIR CONDITIONER SYSTEM
Control System DiagramINFOID:0000000005147675
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:0000000005147676
CONTROL OPERATION
AWIIA0088GB
Revision: April 20092010 QX56

HAC-26
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
MODE DOOR MOTOR
The mode door motor (front) is attached to the heater & cooling unit
assembly. It rotates so that air is discharged from the outlet as indi-
cated by the A/C auto amp. Motor rotation is conveyed to a link
which activates the mode door.
Mode Door Motor (Front)
Component Function CheckINFOID:0000000005147688
INSPECTION FLOW
1.CONFIRM SYMPTOM BY PERFORMING OP ERATIONAL CHECK - DISCHARGE AIR
1. Press mode switch four times and then press the (DEF) switch. Each position indicator should change shape (on display).
2. Confirm that discharge air comes out according to the air distribution table. Refer to HAC-16, "
Discharge
Air Flow (Front)".
NOTE:
Confirm that the compressor clutch is engaged (visual inspection) and intake door position is at FRESH
when DEF ( ) or D/F ( ) is selected.
Is the inspection result normal?
YES >> Inspection End.
NO >> Go to diagnosis procedure. Refer to HAC-26, "
Mode Door Motor (Front) Diagnosis Procedure".
Mode Door Motor (Front) Diagnosis ProcedureINFOID:0000000005147689
Regarding Wiring Diagram information, refer to HAC-91, "Wiring Diagram".
SYMPTOM:• Air outlet does not change.
• Mode door motor does not operate normally.
1.CHECK A/C AUTO AMP. FOR POWER AND GROUND
1. Turn ignition switch ON.
2. Press the mode switch to the B/L ( ) mode.
3. Check voltage between A/C auto amp. harness connector M49 terminal 19 and terminal 20 while pressing the mode switch to
the floor ( ) mode.
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 2.
2.CHECK MODE DOOR MOTOR CIRCUITS FOR SHORT TO GROUND
WJIA0587E
Connector Te r m i n a l s
Condition Voltage
(Approx.)
(+) (-)
A/C auto amp.: M49 20
19Press
mode
switch Battery
voltage
AWIIA0095ZZ
Revision: April 20092010 QX56

HAC-32
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
AIR MIX DOOR MOTOR
Air Mix Door Motor (Driver) Diagnosis Procedure
INFOID:0000000005147692
Regarding Wiring Diagram information, refer to HAC-91, "Wiring Diagram".
SYMPTOM:
• Discharge air temperature does not change.
• Air mix door motor does not operate.
DIAGNOSTIC PROCEDURE FOR AIR MIX DOOR MOTOR (DRIVER)
1.CHECK A/C AUTO AMP. FOR POWER AND GROUND
1. Turn ignition switch ON.
2. Rotate temperature control dial (driver) to 32 °C (90° F).
3. Check voltage between A/C auto amp. harness connector M49
terminal 17 and terminal 18 while rotating temperature control
dial (driver) to 18 °C (60° F).
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 2.
2.CHECK AIR MIX DOOR MOTOR (DRIVE R) CIRCUITS FOR SHORT TO GROUND
1. Turn ignition switch OFF.
2. Disconnect the A/C auto amp. harness connector.
3. Check continuity between A/C auto amp. harness connector M49 terminal 17, 18 and ground.
Is the inspection result normal?
YES >> Replace A/C auto amp. Refer to VTL-7, "Removal and
Installation".
NO >> Repair or replace harness as necessary.
3.CHECK A/C AUTO AMP. FOR POWER AND GROUND
1. Turn ignition switch ON.
2. Rotate temperature control dial (driver) to 32 °C (90° F).
3. Check voltage between A/C auto amp. harness connector M49 terminal 17 and terminal 18 while rotating temperature control
dial (driver) to 18 °C (60° F).
Is the inspection result normal?
YES >> GO TO 4.
NO >> Replace A/C auto amp. Refer to VTL-7, "
Removal and Installation".
ConnectorTe r m i n a l s
Condition Voltage
(Approx.)
(+) (-)
A/C auto amp.: M49 17 18
Rotate temp
control dial Battery
voltage
AWIIA0112ZZ
17 - Ground : Continuity should not exist.
18 - Ground : Continuity should not exist.
AWIIA0114ZZ
Connector Te r m i n a l s
Condition Voltage
(Approx.)
(+) (-)
A/C auto amp.: M49 18 17 Rotate temp
control dial Battery
voltage
AWIIA0115ZZ
Revision: April 20092010 QX56

AIR MIX DOOR MOTORHAC-35
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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1. Turn ignition switch OFF.
2. Disconnect the air mix door motor (driver) harness connector and A/C auto amp. harness connector.
3. Check continuity between air mix door motor (driver) harness connector M147 (B) terminal 4 and A/C auto amp. harness con-
nector M49 (A) terminal 6.
Is the inspection result normal?
YES >> Replace air mix door motor (driver). Refer to VTL-31,
"Removal and Installation".
NO >> Repair or replace harness as necessary.
Air Mix Door Motor (Passen ger) Component Function CheckINFOID:0000000005272349
INSPECTION FLOW
1.CONFIRM SYMPTOM BY PERFORMING OPERAT IONAL CHECK - TEMPERATURE INCREASE
1. Turn the temperature control dial (passenger) 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 (passenger) counterclockwise until 18° C (60°F) is displayed.
2. Check for cold air at discharge air outlets.
Is the inspection result normal?
YES >> Inspection End.
NO >> Go to diagnosis procedure. Refer to HAC-35, "
Air Mix Door Motor (Passenger) Diagnosis Proce-
dure".
Air Mix Door Motor (Passe nger) Diagnosis ProcedureINFOID:0000000005147693
Regarding Wiring Diagram information, refer to HAC-91, "Wiring Diagram".
SYMPTOM:
• Discharge air temperature does not change.
• Air mix door motor does not operate.
DIAGNOSTIC PROCEDURE FOR AIR MIX DOOR MOTOR (PASSENGER)
1.CHECK A/C AUTO AMP. FOR POWER AND GROUND
1. Turn ignition switch ON.
2. Rotate temperature control dial (passenger) to 32 °C (90 °F).
3. Check voltage between A/C auto amp. harness connector M49
terminal 14 and terminal 2 while rotating temperature control dial
(passenger) to 18 ° C (60 °F).
Is the inspection result normal?
OK >> GO TO 3. Continuity should exist.
AWIIA0124ZZ
Connector
Te r m i n a l s
Condition Voltage
(Approx.)
(+) (-)
A/C auto amp.: M49 2 14 Rotate temp
control dial Battery
voltage
AWIIA0125ZZ
Revision: April 20092010 QX56

HAC-40
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
INTAKE DOOR MOTOR
COMPONENT DESCRIPTION
Intake door motor
The intake door motor is attached to the intake unit. It rotates so that
air is drawn from inlets set by the A/C auto amp. Motor rotation is
conveyed to a lever which activates the intake door.
Intake Door Motor Component Function CheckINFOID:0000000005147695
INSPECTION FLOW
1.CONFIRM SYMPTOM BY PERFORMING
OPERATIONAL CHECK - REC ( )
1. Press the mode switch to vent mode( ).
2. Press REC ( ) switch. The REC ( ) indicator should illuminate.
3. Press REC ( ) switch again. The REC ( ) indicator should go out.
4. Listen for intake door position change (you should hear blower sound change slightly).
Is the inspection result normal?
YES >> Inspection End.
NO >> Go to diagnosis procedure. Refer to HAC-40, "
Intake Door Motor Diagnosis Procedure".
Intake Door Motor Diagnosis ProcedureINFOID:0000000005147696
Regarding Wiring Diagram information, refer to HAC-91, "Wiring Diagram".
SYMPTOM:
• Intake door does not change.
• Intake door motor does not operate normally.
DIAGNOSTIC PROCEDURE FOR INTAKE DOOR MOTOR
1.CHECK A/C AUTO AMP. FOR POWER AND GROUND
1. Turn ignition switch ON.
2. Check voltage between A/C auto amp. harness connector M49 terminal 21 and terminal 22 while placing the HVAC system into
self-diagnostic mode.
Is the inspection result normal?
OK >> GO TO 3.
NO >> GO TO 2.
2.CHECK INTAKE DOOR MOTOR CIRCUITS FOR SHORT TO GROUND
WJIA0552E
Connector Te r m i n a l s
Condition Voltage
(Approx.)
(+) (-)
A/C auto amp.: M49 21
22Self-diagnostic
mode Battery volt-
age
AWIIA0146ZZ
Revision: April 20092010 QX56

DEFROSTER DOOR MOTOR CIRCUITHAC-43
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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Defroster Door Motor Co mponent Function CheckINFOID:0000000005147698
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).
Is the inspection result normal?
YES >> Inspection End.
NO >> Go to diagnosis procedure. Refer to HAC-43, "
Defroster Door Motor Diagnosis Procedure".
Defroster Door Motor Diagnosis ProcedureINFOID:0000000005147699
Regarding Wiring Diagram information, refer to HAC-91, "Wiring Diagram".
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.
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 2.
2.CHECK DEFROSTER DOOR MOTOR CIRCUITS FOR SHORT TO GROUND
1. Turn ignition switch OFF.
2. Disconnect the A/C auto amp. harness connector.
3. Check continuity between A/C auto amp. harness connector M49 terminal 23, 24 and ground.
Is the inspection result normal?
YES >> Replace A/C auto amp. Refer to VTL-7, "Removal and
Installation".
NO >> Repair or replace harness as necessary.
3.CHECK A/C AUTO AMP. FOR GROUND AND POWER
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
23 - Ground : Continuity should not exist.
24 - Ground : Continuity should not exist.
AWIIA0153ZZ
Revision: April 20092010 QX56

HAC-48
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
BLOWER MOTOR CONTROL SYSTEM
Blower Speed Compensation - Sunload
When the in-vehicle temperature and the set temperature
are very close, the blower will be operating at low
speed. The speed will vary depending on the sunload. During conditions of low or no sunload, the blower
operates at low speed. During high sunload conditions, the A/C auto amp. causes the blower speed to
increase.
Blower Speed Control Specification
COMPONENT DESCRIPTION
Variable Blower Control
The variable blower control is located on the cooling unit. The vari-
able blower control receives a gate voltage from the A/C auto amp.
to steplessly maintain the blower motor voltage in the 0 to 5 volt
range (approx.).
Front Blower Motor Co mponent Function CheckINFOID:0000000005147701
INSPECTION FLOW
1.CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - FRONT BLOWER
1. Push blower motor (+) switch. Blower motor should operate.
2. Push blower motor (+) switch and continue checking blower speed and fan symbol until all speeds are checked.
Is the inspection result normal?
YES >> Inspection End.
NO >> Go to diagnosis procedure. Refer to HAC-48, "
Front Blower Motor Diagnosis Procedure".
Front Blower Motor Diagnosis ProcedureINFOID:0000000005147702
Regarding Wiring Diagram information, refer to HAC-91, "Wiring Diagram".
SYMPTOM: Blower motor operation is malfunctioning.
DIAGNOSTIC PROCEDURE FOR BLOWER MOTOR
WJIA0441E
WJIA0559E
Revision: April 20092010 QX56

HAC-54
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
BLOWER MOTOR CONTROL SYSTEM
1.CHECK FOR SERVICE BULLETINS
Check for any service bulletins.
>> GO TO 2.
2.CONFIRM SYMPTOM BY PERFORMING REAR BLOW ER MOTOR OPERATIONAL CHECK FROM REAR
AIR CONTROL (FRONT)
1. Turn ignition switch ON.
2. Turn the rear air control (front) blower control dial to the lowest speed and check for rear blower operation
(REAR CTRL indicator off).
3. Continue checking that rear blower speed increases as the rear blower control dial is rotated clockwise.
Does the rear blower motor operate correctly?
YES >> GO TO 3.
NO >> Check the rear blower motor operation. Refer to HAC-53, "
Rear Blower Motor Component Func-
tion Check".
3.CONFIRM SYMPTOM BY PERFORMING REAR BLOWER MOTOR OPERATIONAL CHECK FROM
REAR AIR CONTROL (REAR)
1. Press the REAR CTRL switch (indicator on) on the rear air control (front) to send control of the rear blower
motor back the rear air control (rear).
2. Turn the rear air control (rear) blower control dial to the lowest speed and check for rear blower operation.
3. Continue checking that rear blower speed increases as the rear blower control dial is rotated clockwise.
Does the rear blower motor operate correctly?
YES >> GO TO 4.
NO >> • Check the rear air control (rear). Refer to HAC-56, "
Rear Air Control (Rear) Diagnosis Proce-
dure #2".
4.RECHECK FOR ANY SYMPTOMS
Perform a complete operational check for any symptoms. Refer to HAC-5, "
Operational Check (Rear)".
Does another symptom exist?
YES >> Refer to HAC-3, "How to Perform Trouble Diagnosis For Quick And Accurate Repair".
NO >> Inspection End.
Rear Air Control (Front) Diagnosis Procedure #1INFOID:0000000005147706
Regarding Wiring Diagram information, refer to HAC-91, "Wiring Diagram".
REAR BLOWER MOTOR INOPERATIVE/ON AT ALL TIMES.
1.CHECK FUSES
Check 10A fuse [No. 19 (Located in the fuse block J/B)].
Is the inspection result normal?
YES >> GO TO 2.
NO >> GO TO 6.
2.CHECK REAR AIR CONTRO L (FRONT) POWER SUPPLY
Fuse is good.
Revision: April 20092010 QX56

HAC-56
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
BLOWER MOTOR CONTROL SYSTEM
1. Turn ignition switch OFF.
2. Disconnect rear air control (front), (rear), and A/C auto amp.
connectors.
3. Check continuity between rear air control (front) harness con- nector R108 terminal 1 and ground.
Is the inspection result normal?
YES >> Repair harness or connector for a short.
NO >> System OK.
Rear Air Control (Rear) Diagnosis Procedure #2INFOID:0000000005147707
Regarding Wiring Diagram information, refer to HAC-91, "Wiring Diagram".
REAR AIR CONTROL (REAR) INOPERATIVE
1.CHECK REAR AIR CONTROL (REAR) POWER SUPPLY
1. Disconnect rear air control (rear) harness connector.
2. Turn ignition switch ON.
3. Check voltage between rear air control (rear) harness connector R209 terminal 1 and ground.
Is the inspection results normal?
YES >> GO TO 2.
NO >> Repair harness or connector.
2.CHECK REAR AIR CONTROL (REAR) LIN BUS CIRCUIT
Check voltage between rear air control (rear) harness connector
R209 terminal 5 and ground.
Is the inspection results normal?
YES >> GO TO 3.
NO >> GO TO 4.
3.CHECK REAR AIR CONTROL (REAR) GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Check continuity between rear air control (rear) harness connec- tor R209 terminal 6 and ground.
Is the inspection results normal?
YES >> GO TO 4.
NO >> Repair harness or connector.
4.CHECK REAR AIR CONTROL (REA R) LIN BUS CIRCUIT FOR OPEN
1 - Ground
: Continuity should not exist.
AWIIA0186ZZ
Battery voltage should exist.
AWIIA0182ZZ
Battery voltage should exist.
AWIIA0183ZZ
Continuity should exist.
AWIIA0184ZZ
Revision: April 20092010 QX56

REAR AIR CONTROL SYSTEMHAC-59
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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1. Start and run engine to operating temperature.
2. Turn the rear blower motor to maximum speed from the rear air control (front).
3. Turn rear air control (front) temperature contro l dial clockwise and then counterclockwise (REAR CTRL
indicator off).
4. Check for hot air at rear discharge air outlets in the maximum heat position and cold air at discharge air outlets in the maximum cold position.
Does the rear air control (front) operate properly?
YES >> GO TO 3.
NO >> Check rear air control (front). Refer to HAC-59, "
Air Mix Door Motor (Rear) Diagnosis Procedure".
3.CONFIRM SYMPTOM BY PERFORMING REAR AIR CONTROL (REAR) AIR MIX DOOR MOTOR OPER-
ATIONAL CHECK
1. Press the REAR CTRL switch on rear air control (front) to send control to t he rear air control (rear).
2. Turn rear air control (rear) temperature control dial slowly clockwise and then counterclockwise (REAR
CTRL indicator on).
3. Check for hot air at rear discharge air outlets in the maximum heat position and cold air at rear discharge
air outlets in the maximum cold position.
Does the rear air control (rear) operate properly?
YES >> GO TO 4.
NO >> Check rear air control (rear). Refer to HAC-56, "
Rear Air Control (Rear) Diagnosis Procedure #2".
4.CONFIRM SYMPTOM BY PERFORMING REAR AIR CONTROL (FRONT) MODE OPERATIONAL CHECK
1. Press the REAR CTRL switch on rear air control (front) (REAR CTRL indicator off).
2. Press each mode switch and check for proper air discharge at the appropriate locations.
Does the rear air control (front) operate properly?
YES >> GO TO 5.
NO >> Check mode door motor (rear). Refer to HAC-63, "
Mode Door Motor (Rear) Diagnosis Proce-
dure".
5.CONFIRM SYMPTOM BY PERFORMING REAR AIR CONTROL (REAR) MODE OPERATIONAL CHECK
1. Press the REAR CTRL switch on rear air control (front) to send control to t he rear air control (rear).
2. Press each mode switch and check for proper air discharge at the appropriate locations.
Does the rear air control (rear) operate properly?
YES >> System OK.
NO >> Replace rear air control (rear). Refer to VTL-7, "
Removal and Installation".
Air Mix Door Motor (Rear) Diagnosis ProcedureINFOID:0000000005147711
Regarding Wiring Diagram information, refer to HAC-91, "Wiring Diagram".
SYMPTOM:
• Temperature control (rear) operation is malfunctioning.
DIAGNOSTIC PROCEDURE FOR INOPERATIVE AIR MIX DOOR MOTOR (REAR)
1.CHECK REAR AIR CONTROL (FRONT) POWER SUPPLY
1. Disconnect rear air control (front) harness connector.
2. Turn ignition switch ON.
3. Check voltage between rear air control (front) harness connec- tor R108 terminal 1 and ground.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair harness or connector. Battery voltage should exist.
AWIIA0182ZZ
Revision: April 20092010 QX56