INFINITI QX56 2010 Factory Service Manual

BLOWER MOTOR CONTROL SYSTEMHAC-51
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YES >> Replace variable blower control (front). Refer to VTL-15, "Removal and Installation".
NO >> Replace front blower motor. Refer to VTL-12, "
Removal and Installation".
10.CHECK FRONT BLOWER MOTOR
Check front blower motor. Refer to HAC-52, "
Front Blower Motor Component Inspection".
Is the inspection result normal?
YES >> GO TO 11.
NO >> Replace front blower motor. Refer to VTL-12, "
Removal and Installation".
11 .CHECK BLOWER MOTOR GROUND CIRCUIT
1. Disconnect variable blower control connector.
2. Check continuity between front blower motor harness connector M62 (B) terminal 1 and variable blower control harness connec-
tor M122 (A) terminal 2.
Is the inspection result normal?
YES >> GO TO 12.
NO >> Repair harness or connector.
12.CHECK VARIABLE BLOWER CONTRO L POWER SUPPLY CIRCUIT FOR OPEN
1. Disconnect front blower motor relay.
2. Check continuity between front blower motor relay harness con- nector M107 (A) terminals 3 and variable blower control harness
connector M122 (B) terminal 4.
Is the inspection result normal?
YES >> GO TO 13.
NO >> Repair harness or connector.
13.CHECK VARIABLE BLOWER CONTROL GROUND CIRCUIT
Check continuity between variable blower control harness connector
M122 terminal 1 and ground.
Is the inspection result normal?
YES >> GO TO 14.
NO >> Repair harness or connector.
14.CHECK VARIABLE BLOWER CONTROL SIGNAL CIRCUIT 1 - 2 : Continuity should exist.
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3 - 4
: Continuity should exist.
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1 - Ground: Continuity should exist.
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HAC-52
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
BLOWER MOTOR CONTROL SYSTEM
1. Reconnect all disconnected component connectors.
2. Disconnect A/C auto amp. connector.
3. Turn ignition switch ON.
4. Press the blower (+) switch to maximum speed.
5. Check voltage between A/C auto amp. harness connector M49
terminal 13 and ground.
Is the inspection result normal?
YES >> Replace A/C auto amp. Refer to VTL-7, "Removal and
Installation".
NO >> GO TO 15.
15.CHECK VARIABLE BLOWER CONT ROL SIGNAL CIRCUIT FOR OPEN
1. Disconnect variable blower control connector.
2. Check continuity between A/C auto amp. harness connector M49 (B) terminal 13 and variable blower control harness con-
nector M122 (A) terminal 3.
Is the inspection result normal?
YES >> Replace variable blower control. Refer to VTL-15,
"Removal and Installation".
NO >> Repair harness or connector.
Front Blower Motor Component InspectionINFOID:0000000005147703
COMPONENT INSPECTION
Check continuity between terminals by supplying 12 volts and
ground to coil side terminals of relay.
Front Blower Motor
13 - Ground : Approx. 4.5V
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13 - 3: Continuity should exist.
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WJIA1401E
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BLOWER MOTOR CONTROL SYSTEMHAC-53
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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:0000000005147704
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
System Operation
Rear Blower Control
When the rear blower control dial (front) REAR CTRL s witch 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 speed regardless of the rear air control (rear) position.
Rear Blower Motor Co mponent Function CheckINFOID:0000000005147705
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
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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.
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BLOWER MOTOR CONTROL SYSTEMHAC-55
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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
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
Battery voltage should exist.
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Battery voltage should exist.
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Continuity should exist.
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Continuity should exist.
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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.
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Battery voltage should exist.
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Battery voltage should exist.
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Continuity should exist.
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BLOWER MOTOR CONTROL SYSTEMHAC-57
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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:0000000005147708
COMPONENT INSPECTION
Rear Blower Motor Relay
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. Continuity should exist.
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HAC-58
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
REAR AIR CONTROL SYSTEM
REAR AIR CONTROL SYSTEM
Rear Air Control System DescriptionINFOID:0000000005147709
SYSTEM DESCRIPTION
Component Parts
Rear air control sy
stem 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 mo tor speeds and the rear temperature and mode operations.
Rear Air Control Component Function CheckINFOID:0000000005147710
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 CO NTROL (FRONT) AIR MIX DOOR MOTOR OP-
ERATIONAL CHECK
AWIIA0197GB
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REAR AIR CONTROL SYSTEMHAC-59
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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
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HAC-60
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
REAR AIR CONTROL SYSTEM
2.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 3.
NO >> GO TO 4.
3.CHECK REAR AIR CONTRO L (FRONT) GROUND CIRCUIT
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.
4.CHECK LIN BUS VOLTAGE CIRCUIT FOR OPEN
1. Turn ignition switch OFF.
2. Disconnect the mode door motor (rear) harness connector.
3. Check continuity between rear air control (front) harness con- nector R108 (B) terminal 5 and A/C auto amp. harness connec-
tor M50 (A) terminal 48.
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.
5.CHECK A/C AUTO AMP. FOR POWER AND GROUND FOR AIR MIX DOOR MOTOR (REAR)
1. Reconnect all disconnected parts.
2. Turn ignition switch ON.
3. Rotate temperature control dial (rear) to maximum heat.
4. Check voltage between A/C auto amp. harness connector M50 terminal 49 and terminal 50 while rotating temperature control
dial (front) to maximum cold.
Is the inspection result normal?
YES >> GO TO 9.
NO >> GO TO 6.
6.CHECK AIR MIX DOOR MOTOR (REAR) CIRCUITS FOR OPEN
Battery voltage should exist.
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Continuity should exist.
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48 - 5
: Continuity should exist.
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Connector Te r m i n a l s
Condition Voltage
(Approx.)
(+) (-)
A/C auto amp.: M50 49 50
Rotate temp
control dial Battery
voltage
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