2008 INFINITI QX56 blower motor rear

HAC-14
< FUNCTION DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
AUTOMATIC AIR CONDITIONER SYSTEM
Rear Air Controls
REAR TEMPERATURE CONTROL DIAL (FRONT/REAR)
The temperature increases or decreases the set temperature.
REAR MODE SWITCHES (FRONT/REAR)
Controls the air discharge outlets.
REAR BLOWER CONTROL DIAL (FRONT)
When the REAR CTRL switch is in the off (indicator off)
the rear air control (front) controls the rear blower
motor speed regardless of the rear air control (rear) blow er control dial (rear) position. The rear air control
(front) controls the blower motor speed.
REAR BLOWER CONTROL DIAL (REAR)
When the REAR CTRL switch is in the on (indicator on) the rear air control (rear) controls the rear blower
motor speed regardless of the rear air control (front) blow er control dial (front) position. The rear air control
(rear) controls the blower motor speed.
MAGNET CLUTCH CONTROL
When A/C switch or DEF switch is pressed, A/ C auto amp. inputs compressor ON signal to BCM.
BCM sends compressor ON signal to ECM and A/C auto amp., via CAN communication line.
ECM judges whether compressor can be turned ON, based on each sensor status (refrigerant pressure sen-
sor signal, throttle angle sensor, etc.). If it judges co mpressor can be turned ON, it sends compressor ON sig-
nal to IPDM E/R, via CAN communication line.
AWIIA0082ZZ
1. Rear air control (front )2. Rear air control (rear)
AWIIA0089GB
Revision: March 2010 2008 QX56

BLOWER MOTOR CONTROL SYSTEMHAC-55
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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Check continuity between terminals by supplying 12 volts and
ground to coil side terminals of relay.
Front Blower Motor
Confirm smooth rotation of the blower motor.
• Ensure that there are no foreign particles inside the blower unit.
• Apply 12 volts to terminal 2 and ground to terminal 1 and verify that the motor operates freely and quietly.
Rear Blower Motor DescriptionINFOID:0000000001679799
SYSTEM DESCRIPTION
Component Parts
Rear blower speed control system components are:
• A/C auto amp.
• A/C and AV switch assembly
• Rear air control (front)
• Rear air control (rear)
• Variable blower control (rear)
• Rear blower motor
• Rear blower motor relay
WJIA1401E
WJIA1508E
Revision: March 2010 2008 QX56

HAC-56
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
BLOWER MOTOR CONTROL SYSTEM
System Operation
Rear Blower Control
When the rear blower control dial (front) REAR CTRL switch is pressed (indicator on), it allows the rear air
control (rear) to control the rear blower motor speed. If t
he REAR CTRL switch is off (indicator off), the rear air
control (front) controls the rear blower motor s peed regardless of the rear air control (rear) position.
Rear Blower Motor Component Function CheckINFOID:0000000001679800
INSPECTION FLOW
SYMPTOM:
• Rear blower motor does not operate from the rear air control (front) and the rear air control (rear).
• Rear blower motor operates from rear air control (front) only.
• Rear blower motor operates in high at all times.
INSPECTION FLOW
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-56, "
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.
AWIIA0181GB
Revision: March 2010 2008 QX56

BLOWER MOTOR CONTROL SYSTEMHAC-57
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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NO >> • Check the rear air control (rear). Refer to HAC-58, "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:0000000001679801
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 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 3.
NO >> Repair harness or connector.
3.CHECK REAR AIR CONTROL (FRONT) LIN BUS VOLTAGE
Check voltage between rear air control (front) harness connector
R108 terminal 5 and ground.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair harness or connector.
4.CHECK REAR AIR CONTROL (FRONT) GROUND CIRCUIT Fuse is good.
Battery voltage should exist.
AWIIA0182ZZ
Battery voltage should exist.
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Revision: March 2010
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HAC-58
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
BLOWER MOTOR CONTROL SYSTEM
1. Turn ignition switch OFF.
2. Check continuity between rear air control (front) harness con-
nector R108 terminal 6 and ground.
Is the inspection result normal?
YES >> GO TO 5.
NO >> Repair harness or connector.
5.CHECK REAR AIR CONTROL (FRO NT) LIN BUS CIRCUIT FOR OPEN
1. Disconnect A/C auto amp. connector.
2. Check continuity between A/C auto amp. harness connector M50 (A) terminal 48 and rear air control (front) harness connec-
tor R108 (B) terminal 5.
Is the inspection result normal?
YES >> Replace A/C auto amp. Refer to VTL-7, "Removal and
Installation".
NO >> Repair harness or connector.
6.REPLACE FUSE
1. Replace fuse.
2. Activate the rear blower motor.
Does the fuse blow?
YES >> GO TO 7.
NO >> Inspection End.
7.CHECK REAR AIR CONTROL (FRONT) POWER SUPPLY CIRCUIT FOR SHORT
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:0000000001679802
REAR AIR CONTROL (REAR) INOPERATIVE
1.CHECK REAR AIR CONTRO L (FRONT) POWER SUPPLY
Continuity should exist.
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Continuity should exist.
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1 - Ground
: Continuity should not exist.
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Revision: March 2010 2008 QX56

BLOWER MOTOR CONTROL SYSTEMHAC-59
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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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 (FRONT) LIN BUS CIRCUIT
Check voltage between rear air control (front) 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 (FRONT) GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Check continuity between rear air control (front) harness con- nector R209 terminal 6 and ground.
Is the inspection results normal?
YES >> GO TO 4.
NO >> Repair harness or connector.
4.CHECK REAR AIR CONTROL (REAR) LIN BUS CIRCUIT FOR OPEN
1. Disconnect A/C auto amp. connector.
2. Check continuity between A/C auto amp. harness connector M50 (A) terminal 47 and rear air control (rear) harness connec-
tor R209 (B) terminal 5.
Is the inspection results normal?
YES >> Replace A/C auto amp. Refer to VTL-7, "Removal and
Installation".
NO >> Repair harness or connector.
Rear Blower Motor Component Inspection INFOID:0000000001679803
COMPONENT INSPECTION
Rear Blower Motor Relay
Battery voltage should exist.
AWIIA0182ZZ
Battery voltage should exist.
AWIIA0183ZZ
Continuity should exist.
AWIIA0184ZZ
Continuity should exist.
AWIIA0187ZZ
Revision: March 2010 2008 QX56

HAC-60
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
BLOWER MOTOR CONTROL SYSTEM
Check circuit continuity between terminals by supplying 12 volts and
ground to coil side terminals of relays.
Rear Blower Motor
Check that there are no foreign particles inside the intake unit.
Apply 12 volts to terminal 2 and ground to terminal 1 and ensure that
the blower motor rotates freely and quietly.
WJIA0973E
WJIA1508E
Revision: March 2010
2008 QX56

REAR AIR CONTROL SYSTEMHAC-61
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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REAR AIR CONTROL SYSTEM
Rear Air Control System DescriptionINFOID:0000000001679804
SYSTEM DESCRIPTION
Component Parts
Rear air control system components are:
• A/C auto amp.
• Rear air control (front)
• Rear air control (rear)
• Air mix door motor (rear)
• Mode door motor (rear)
System Operation
Rear Air Control
When the REAR CTRL indicator is off the rear air cont rol (front) will control all rear blower motor speeds and
the rear temperature and mode operations. When the REAR CTRL switch is pressed (indicator on), the rear
air control (rear) will control all the rear blower motor speeds and the rear temperature and mode operations.
Rear Air Control Component Function CheckINFOID:0000000001679805
SYMPTOM:
• Temperature cannot be adjusted from the rear air controls.
• Mode cannot be adjusted from the rear air controls.
INSPECTION FLOW
1.CHECK FOR SERVICE BULLETINS
Check for any service bulletins.
>> GO TO 2.
2.CONFIRM SYMPTOM BY PERFORMING REAR AIR CONTROL (FRONT) AIR MIX DOOR MOTOR OP-
ERATIONAL CHECK
AWIIA0197GB
Revision: March 2010 2008 QX56