2011 INFINITI QX56 air conditioning

HAC-118
< DTC/CIRCUIT DIAGNOSIS >[AUTOMATIC AIR CONDITIONING]
DOOR MOTOR
DOOR MOTOR
Diagnosis ProcedureINFOID:0000000006275966
1.CHECK EACH DOOR MOTOR POWER SUPPLY
1. Turn ignition switch ON.
2. Check voltage between intake door motor harness connector and ground.
Is the inspection result normal?
YES >> GO TO 2.
NO >> GO TO 3.
2.CHECK EACH DOOR MOTOR GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect intake door motor connector.
3. Check continuity between intake door motor harness connector and ground.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Repair harness or connector.
3.CHECK EACH DOOR MOTOR POWER SUPPLY CIRCUIT FOR OPEN
1. Disconnect A/C auto amp. connector.
2. Check continuity between intake door motor harness connector and A/C auto amp. harness connector.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair harness or connector.
4.CHECK EACH DOOR MOTOR POWER SUPPLY CIRCUIT FOR SHORT
1. Disconnect following connectors.
- Front air mix door motor LH
- Front air mix door motor RH
- Front mode door motor
- Upper vent door motor
- Rear air mix door motor
- Rear mode door motor
2. Check continuity between intake door motor harness connector and ground.
Is the inspection result normal?
+
−Vo l ta g e
(Approx.)
Intake door motor
Connector Terminal M254 1 Ground 12 V
Intake door motor —Continuity
Connector Terminal
M254 2 Ground Existed
Intake door motor A/C auto amp. Continuity
Connector Terminal Connector Terminal
M254 1 M50 17 Existed
Intake door motor —Continuity
Connector Terminal
M254 1 Ground Not existed
Revision: 2010 May2011 QX56

DOOR MOTORHAC-119
< DTC/CIRCUIT DIAGNOSIS > [AUTOMATIC AIR CONDITIONING]
C
D
E
F
G H
J
K L
M A
B
HAC
N
O P
YES >> Replace A/C auto amp.. Refer to HAC-146, "Removal and Installation".
NO >> Repair harness or connector.
Revision: 2010 May2011 QX56

HAC-120
< DTC/CIRCUIT DIAGNOSIS >[AUTOMATIC AIR CONDITIONING]
DOOR MOTOR COMMUNICATION CIRCUIT
DOOR MOTOR COMMUNICATION CIRCUIT
Diagnosis ProcedureINFOID:0000000006275967
NOTE:
If all of door motor DTCs are detected, check this circuit.
1.CHECK EACH DOOR MOTOR COMMUNICATION SIGNAL
1. Turn ignition switch ON.
2. Check output waveform between A/C auto amp. harness connector and ground with the oscilloscope.
Is the inspection result normal?
YES >> GO TO 2.
NO >> GO TO 3.
2.CHECK EACH DOOR MOTOR COMMUNICA TION SIGNAL CIRCUIT FOR OPEN
1. Turn ignition switch OFF.
2. Disconnect A/C auto amp. connecto r and intake door motor connector.
3. Check continuity between A/C auto amp. harness connector and intake door motor harness connector.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Repair harness or connector.
3.CHECK EACH DOOR MOTOR COMMUNICA TION SIGNAL CIRCUIT FOR SHORT
1. Disconnect following connectors.
- Front air mix door motor LH
- Front air mix door motor RH
- Front mode door motor
- Upper vent door motor
- Rear air mix door motor
- Rear mode door motor
2. Check continuity between A/C auto amp. harness connector and ground.
Is the inspection result normal?
YES >> Replace A/C auto amp.. Refer to HAC-146, "Removal and Installation".
NO >> Repair harness or connector.
+
−Output waveform
A/C auto amp.
Connector Terminal
M50 16 Ground
SJIA1453J
A/C auto amp. Intake door motor Continuity
Connector Terminal Connector Terminal
M50 16 M254 3 Existed
A/C auto amp. —Continuity
Connector Terminal
M50 16 Ground Not existed
Revision: 2010 May2011 QX56

FRONT BLOWER MOTORHAC-121
< DTC/CIRCUIT DIAGNOSIS > [AUTOMATIC AIR CONDITIONING]
C
D
E
F
G H
J
K L
M A
B
HAC
N
O P
FRONT BLOWER MOTOR
Diagnosis ProcedureINFOID:0000000006275968
1.CHECK FUSE
1. Turn ignition switch OFF.
2. Check 15A fuse [No. 21 and 22, located in fuse block (J/B)]. NOTE:
Refer to PG-140, "
Fuse, Connector and Terminal Arrangement".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Replace the blown fuse after repairing the affected circuit if a fuse is blown.
2.CHECK FRONT BLOWER MOTOR POWER SUPPLY
1. Disconnect front blower motor connector.
2. Turn ignition switch ON.
3. Check voltage between front blower motor harness connector and ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 6.
3.CHECK FRONT BLOWER MOTOR GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Check continuity between front blower motor harness connector and ground.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair harness or connector.
4.CHECK FRONT BLOWER MOTOR CONTROL SIGNAL CIRCUIT
1. Disconnect A/C auto amp. connector.
2. Check continuity between front blower motor harness connector and A/C auto amp. harness connector.
Is the inspection result normal?
YES >> GO TO 5.
NO >> Repair the harness or connector.
5.CHECK FRONT BLOWER MOTOR CONTROL SIGNAL
1. Reconnect front blower motor connector and A/C auto amp. connector.
2. Turn ignition switch ON.
3. Operate MODE switch to set air outlet to VENT.
4. Change fan speed from Lo to Hi, and check duty rati os between front blower motor harness connector
and ground by using an oscilloscope.
+
−Vol tag e
Front blower motor
Connector Terminal M272 1 Ground Battery voltage
Front blower motor —Continuity
Connector Terminal
M272 3 Ground Existed
Front blower motor A/C auto amp. Continuity
Connector Terminal Connector Terminal
M272 2 M50 14 Existed
Revision: 2010 May2011 QX56

HAC-122
< DTC/CIRCUIT DIAGNOSIS >[AUTOMATIC AIR CONDITIONING]
FRONT BLOWER MOTOR
NOTE:
Calculate drive signal duty ratio as shown in the figure.
T2 = Approx. 1.6 ms
Is the inspection result normal?
YES >> Replace front blower motor. Refer to VTL-16, "FRONT A/C UNIT : Removal and Installation".
NO >> Replace A/C auto amp.. Refer to HAC-146, "
Removal and Installation".
6.CHECK BLOWER RELAY GROUND CIRCUIT
Check continuity between fuse bl ock (J/B) harness connector and ground.
Is the inspection result normal?
YES >> GO TO 7.
NO >> Repair harness or connector.
7.CHECK BLOWER RELAY
Check blower relay. Refer to HAC-123, "
Component Inspection (Blower Relay)".
Is the inspection result normal?
YES >> Repair harness or connector between front blower motor and fuse block (J/B).
NO >> Replace blower relay.
Component Inspection (Front Blower Motor)INFOID:0000000006275969
1.CHECK FRONT BLOWER MOTOR-I
1. Remove front blower motor.
2. Check that there is not any mixing foreign object in the front blower motor.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Replace front blower motor. Refer to VTL-16, "
FRONT A/C UNIT : Removal and Installation".
2.CHECK FRONT BLOWER MOTOR-II
Check that there is not breakage or damage in the front blower motor.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Replace front blower motor. Refer to VTL-16, "
FRONT A/C UNIT : Removal and Installation".
3.CHECK FRONT BLOWER MOTOR-III
Check that front blower motor turns smoothly.
Is the inspection result normal?
YES >> INSPECTION END
Front blower motor Condition Duty ratio
(Approx.)
Connector Terminal Fan speed (manual)
VENT mode
M272 2 1st 25 %
2nd 33 % 3rd 41 %4th 51 %
5th 61 %
6th 69 %
7th 81 %
JPLIA1210GB
Fuse block (J/B) —Continuity
Connector Terminal
M3 7C Ground Existed
Revision: 2010 May2011 QX56

FRONT BLOWER MOTORHAC-123
< DTC/CIRCUIT DIAGNOSIS > [AUTOMATIC AIR CONDITIONING]
C
D
E
F
G H
J
K L
M A
B
HAC
N
O P
NO >> Replace front blower motor. Refer to VTL-16, "FRONT A/C UNIT : Removal and Installation".
Component Inspection (Blower Relay)INFOID:0000000006275970
1.CHECK BLOWER RELAY
1. Turn ignition switch OFF.
2. Remove blower relay.
3. Check continuity between blower relay terminal 3 and 5 when voltage is supplied between terminal 1 and 2.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace blower relay.
Terminal Voltage Continuity
35 ON Existed
OFF Not existed
JSIIA1551ZZ
Revision: 2010 May2011 QX56

HAC-124
< DTC/CIRCUIT DIAGNOSIS >[AUTOMATIC AIR CONDITIONING]
IONIZER
IONIZER
Component Function CheckINFOID:0000000006275971
1.CHECK IONIZER OPERATION SOUND
1. Turn ignition switch ON.
2. Check ionizer operation sound (whirri ng sound) in duct by putting an ear to the side ventilator grille (driver
side) outlet while pressing fan switch and OFF switch alternately.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Refer to HAC-124, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000006275972
1.CHECK FUSE
1. Turn ignition switch OFF.
2. Check 10A fuse [No.4, located in fuse block (J/B)]. NOTE:
Refer to PG-140, "
Fuse, Connector and Terminal Arrangement".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Replace the blown fuse after repairing the affected circuit if a fuse is blown.
2.CHECK IONIZER POWER SUPPLY
1. Disconnect ionizer connector.
2. Turn ignition switch ON.
3. Check voltage between ionizer harness connector and ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair harness or connector between ionizer and fuse block (J/B).
3.CHECK IONIZER GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Check continuity between ionizer harness connector and ground.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair harness or connector.
4.CHECK IONIZER (ON/OFF) CONTROL SIGNAL CIRCUIT
1. Connect ionizer connector.
2. Disconnect A/C auto amp. connector.
3. Turn ignition switch ON.
4. Check voltage between A/C auto amp. harness connector and ground.
+
−Voltag e
Ionizer
Connector Terminal M130 1 Ground Battery voltage
Ionizer —Continuity
Connector Terminal
M130 3 Ground Existed
Revision: 2010 May2011 QX56

IONIZER
HAC-125
< DTC/CIRCUIT DIAGNOSIS > [AUTOMATIC AIR CONDITIONING]
C
D
E
F
G H
J
K L
M A
B
HAC
N
O P
Is the inspection result normal?
YES >> Replace A/C auto amp.. Refer to HAC-146, "Removal and Installation".
NO >> GO TO 5.
5.CHECK IONIZER (ON/OFF) CONT ROL SIGNAL CIRCUIT FOR OPEN
1. Turn ignition switch OFF.
2. Disconnect ionizer connector.
3. Check continuity between A/C auto amp. harness connector and ionizer harness connector.
Is the inspection result normal?
YES >> GO TO 6.
NO >> Repair harness or connector.
6.CHECK IONIZER (ON/OFF) CONT ROL SIGNAL CIRCUIT FOR SHORT
Check continuity between A/C aut o amp. harness connector and ground.
Is the inspection result normal?
YES >> Replace ionizer. Refer to HAC-155, "Removal and Installation".
NO >> Repair harness or connector.
+
−Vo l ta g e
A/C auto amp.
Connector Terminal M50 5 Ground Battery voltage
A/C auto amp. Ionizer Continuity
Connector Terminal Connector Terminal
M50 5 M130 4 Existed
A/C auto amp. —Continuity
Connector Terminal
M50 5 Ground Not existed
Revision: 2010 May2011 QX56