INFINITI QX56 2009 Factory Service Manual

HAC-58
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
BLOWER MOTOR CONTROL SYSTEM
NO >> • Check the rear air control (rear). Refer to
HAC-59, "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:0000000003775362
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
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 CONTRO L (FRONT) GROUND CIRCUIT
Fuse is good.
Battery voltage should exist.
AWIIA0182ZZ
Battery voltage should exist.
AWIIA0183ZZ
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BLOWER MOTOR CONTROL SYSTEMHAC-59
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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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 (Rea r) Diagnosis Procedure #2INFOID:0000000003775363
REAR AIR CONTROL (REAR) INOPERATIVE
1.CHECK REAR AIR CONTROL (REAR) POWER SUPPLYContinuity should exist.
AWIIA0184ZZ
Continuity should exist.
AWIIA0185ZZ
1 - Ground
: Continuity should not exist.
AWIIA0186ZZ
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HAC-60
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
BLOWER MOTOR CONTROL SYSTEM
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. 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:0000000003775364
COMPONENT INSPECTION
Rear Blower Motor Relay
Battery voltage should exist.
AWIIA0182ZZ
Battery voltage should exist.
AWIIA0183ZZ
Continuity should exist.
AWIIA0184ZZ
Continuity should exist.
AWIIA0187ZZ
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BLOWER MOTOR CONTROL SYSTEMHAC-61
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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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
AWIIA1086ZZ
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HAC-62
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
REAR AIR CONTROL SYSTEM
REAR AIR CONTROL SYSTEM
Rear Air Control System DescriptionINFOID:0000000003775365
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:0000000003775366
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-63
< 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-63, "
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-59, "
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-67, "
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:0000000003775367
DIAGNOSTIC PROCEDURE FOR INOPERATIVE AIR MIX DOOR MOTOR (REAR)
SYMPTOM:
• Temperature control (rear) operation is malfunctioning.
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.
2.CHECK REAR AIR CONTROL (FRONT) LIN BUS VOLTAGE Battery voltage should exist.
AWIIA0182ZZ
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HAC-64
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
REAR AIR CONTROL SYSTEM
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. Disconnect the mode door motor (rear) harness connector.
2. 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.
AWIIA0183ZZ
Continuity should exist.
AWIIA0184ZZ
48 - 5
: Continuity should exist.
AWIIA0185ZZ
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
AWIIA0135ZZ
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REAR AIR CONTROL SYSTEMHAC-65
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1. Turn ignition switch OFF.
2. Disconnect the A/C auto amp. harness connector.
3. Check continuity between A/C auto amp. harness connector M50 terminal 49 and terminal 50.
Is the inspection result normal?
YES >> Replace A/C auto amp. Refer to VTL-7, "Removal and
Installation".
NO >> GO TO 7.
7.CHECK AIR MIX DOOR MOTOR (REAR) CIRCUITS FOR SHORT TO GROUND
1. Turn ignition switch OFF.
2. Disconnect the air mix door motor (rear) harness connector.
3. Check continuity between A/C auto amp. harness connector M50 terminal 49, 50 and ground.
Is the inspection result normal?
YES >> GO TO 8.
NO >> Repair or replace harness as necessary.
8.CHECK AIR MIX DOOR MOTOR (REAR) CIRCUITS FOR OPEN
1. Disconnect the air mix door motor (rear) harness connector.
2. Check continuity between A/C auto amp. harness connector M50 (A) terminal 49, 50 and the air mix door motor (rear) har-
ness connector B155 (B) terminal 1, 6.
Is the inspection result normal?
YES >> Replace air mix door motor (rear). Refer to VTL-26,
"Removal and Installation".
NO >> Repair or replace harness as necessary.
9.CHECK A/C AUTO AMP. OWER AND GROUND FOR AIR MIX DOOR MOTOR (REAR)
1. Rotate temperature control dial (front) to maximum cold.
2. Check voltage between A/C auto amp. harness connector M50 terminal 49 and terminal 50 while rotating temperature control
dial (rear) to maximum heat.
Is the inspection result normal?
YES >> GO TO 10.
NO >> Replace A/C auto amp. Refer to VTL-7, "
Removal and Installation".
10.CHECK A/C AUTO AMP. FOR AIR MIX DOOR MOTOR (REAR) PBR POWER AND GROUND
Continuity should exist.
AWIIA0138ZZ
49 - Ground
: Continuity should not exist.
50 - Ground : Continuity should not exist.
AWIIA0136ZZ
49 - 1 : Continuity should exist.
50 - 6 : Continuity should exist.
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ConnectorTe r m i n a l s
Condition Voltage
(Approx.)
(+) (-)
A/C auto amp.: M50 50 49 Rotate temp
control dial Battery
voltage
AWIIA0137ZZ
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HAC-66
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
REAR AIR CONTROL SYSTEM
1. Check voltage between A/C auto amp. harness connector M50
(A) terminal 28 and M49 (B) terminal 3.
Is the inspection result normal?
YES >> GO TO 14.
NO >> GO TO 11.
11 .CHECK PBR REFERENCE VOLTAGE AND GROUND CIRCUITS
1. Turn ignition switch OFF.
2. Disconnect the A/C auto amp. harness connector.
3. Check continuity between A/C auto amp. harness connector M50 (A) terminal 28 and M49 (B) terminal 3.
Is the inspection result normal?
YES >> GO TO 13.
NO >> GO TO 12.
12.CHECK PBR REFERENCE VOLTAGE CIRCUIT FOR OPEN
1. Disconnect the air mix door motor (rear) harness connector.
2. Check continuity between air mix door motor (rear) harness con- nector B155 (B) terminal 3, 2 and A/C auto amp. harness con-
nector M50 (A) terminal 28 and M49 (C) terminal 3.
Is the inspection result normal?
YES >> Replace air mix door motor (rear). Refer to VTL-26,
"Removal and Installation".
NO >> Repair or replace harness as necessary.
13.CHECK PBR REFERENCE VOLTAGE CIRCUIT FOR SHORT TO GROUND
Check continuity between A/C auto amp. harness connector M50
terminal 28 and ground.
Is the inspection result normal?
YES >> Replace A/C auto amp. VTL-7, "Removal and Installa-
tion".
NO >> Repair or replace harness as necessary.
14.CHECK PBR FEEDBACK VOLTAGE
Connector Te r m i n a l s
Voltage (Ap-
prox.)
(+) (-)
A/C auto amp.: M49, M50 28 35V
AWIIA0118ZZ
Continuity should exist.
AWIIA0120ZZ
28 - 3 : Continuity should exist.
3 - 2 : Continuity should exist.
AWIIA0121ZZ
Continuity should not exist.
AWIIA0119ZZ
Revision: December 20092009 QX56

REAR AIR CONTROL SYSTEMHAC-67
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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Check voltage between A/C auto amp. harness connector M50 ter-
minal 33 and ground while rotating temperature control dial (rear)
from maximum cold to maximum heat.
Is the inspection result normal?
YES >> System OK.
NO >> GO TO 15.
15.CHECK PBR FEEDBACK CIRCUIT FOR OPEN
1. Turn ignition switch OFF.
2. Disconnect the air mix door motor (rear) harness connector and A/C auto amp. harness connector.
3. Check continuity between air mix door motor (rear) harness con- nector B155 (B) terminal 4 and A/C auto amp. harness connec-
tor M50 (A) terminal 33.
Is the inspection result normal?
YES >> GO TO 16.
NO >> Repair or replace harness as necessary.
16.CHECK PBR FEEDBACK SIGNAL CIRCUIT FOR SHORT TO GROUND
Check continuity between A/C auto amp. harness connector M50
terminal 33 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.
Mode Door Motor (Rea r) Diagnosis ProcedureINFOID:0000000003775368
DIAGNOSTIC PROCEDURE INOPERATIVE MODE 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.
2.CHECK REAR AIR CONTROL (FRONT) LIN BUS VOLTAGE Voltage : Approx. 1V - 4.5V
AWIIA0140ZZ
Continuity should exist.
AWIIA0142ZZ
Continuity should not exist.
AWIIA0141ZZ
Battery voltage should exist.
AWIIA0182ZZ
Revision: December 20092009 QX56