2011 INFINITI QX56 air conditioning

HAC-126
< DTC/CIRCUIT DIAGNOSIS >[AUTOMATIC AIR CONDITIONING]
MAGNET CLUTCH
MAGNET CLUTCH
Component Function CheckINFOID:0000000006275973
1.CHECK MAGNET CLUTCH OPERATION
Perform auto active test of IPDM E/R. Refer to PCS-10, "
Diagnosis Description".
Does it operate normally?
YES >> INSPECTION END
NO >> Refer to HAC-126, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000006275974
1.CHECK FUSE
1. Turn ignition switch OFF.
2. Check 10A fuse (No. 49, located in IPDM E/R). 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 MAGNET CLUTCH POWER SUPPLY CIRCUIT
1. Disconnect compressor connector and IPDM E/R connector.
2. Check continuity between compressor harness connector and IPDM E/R harness connector.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair harness or connector.
3.CHECK MAGNET CLUTCH
Directly apply battery voltage to the magnet clutch. Check operation visually and by sound.
Does it operate normally?
YES >> Replace IPDM E/R. Refer to PCS-32, "Removal and Installation".
NO >> Replace magnet clutch. Refer to HA-31, "
MAGNET CLUTCH : Removal and Installation of Com-
pressor Clutch".
Compressor IPDM E/R
Continuity
Connector Terminal Connector Terminal
F43 1 E15 56 Existed
Revision: 2010 May2011 QX56

REAR A/C CONTROL COMMUNICATION SIGNAL
HAC-127
< DTC/CIRCUIT DIAGNOSIS > [AUTOMATIC AIR CONDITIONING]
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REAR A/C CONTROL COMMUNICATION SIGNAL
Diagnosis ProcedureINFOID:0000000006275975
1.CHECK COMMUNICATION SIGNAL CIRCUIT (A/C AUTO AMP. → REAR A/C CONTROL) FOR OPEN
1. Turn ignition switch OFF.
2. Disconnect rear A/C contro l and A/C auto amp. connector.
3. Check continuity between rear A/C control har ness connector and A/C auto amp. harness connector.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair harness or connector.
2.CHECK COMMUNICATION SIGNAL CIRCUIT (A/C AUTO AMP. → REAR A/C CONTROL) FOR SHORT
Check continuity between rear A/ C control harness connector and ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair harness or connector.
3.CHECK COMMUNICATION SIGNAL CIRCUIT (REAR A/C CONTROL → A/C AUTO AMP.) CIRCUIT FOR
OPEN
Check continuity between rear A/C control har ness connector and A/C auto amp. harness connector.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair harness or connector.
4.CHECK COMMUNICATION SIGNAL CIRCUIT (REAR A/C CONTROL → A/C AUTO AMP.) CIRCUIT FOR
SHORT
Check continuity between rear A/ C control 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.
Rear A/C control A/C auto amp. Continuity
Connector Terminal Connector Terminal
M419M5011 Existed
Rear A/C control —Continuity
Connector Terminal
M41 9 Ground Not existed
Rear A/C control A/C auto amp. Continuity
Connector Terminal Connector Terminal
M4110M5031 Existed
Rear A/C control —Continuity
Connector Terminal
M41 10 Ground Not existed
Revision: 2010 May2011 QX56

HAC-128
< DTC/CIRCUIT DIAGNOSIS >[AUTOMATIC AIR CONDITIONING]
REAR A/C SOLENOID VALVE
REAR A/C SOLENOID VALVE
Diagnosis ProcedureINFOID:0000000006275976
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 REAR A/C SOLENOID VALVE POWER SUPPLY
1. Disconnect rear A/C solenoid valve connector.
2. Turn ignition switch ON and front air conditioning system ON.
3. Check voltage between rear A/C solenoid valve harness connector and ground when rear blower motor is operated.
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 4.
3.CHECK REAR A/C SOLENOID VALVE GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Check continuity between rear A/C solenoid valve harness connector and ground.
Is the inspection result normal?
YES >> Replace rear expansion valve assembly. Refer to HA-49, "EXPANSION VALVE : Removal and
Installation".
NO >> Repair harness or connector.
4.CHECK REAR A/C RELAY POWER SUPPLY
1. Turn ignition switch OFF.
2. Disconnect rear A/C relay connector.
3. Turn ignition switch ON.
4. Check voltage between rear A/C relay harness connector and ground.
Is the inspection result normal?
YES >> GO TO 5.
+
−Condition Vo l ta g e
(Approx.)
Rear A/C solenoid valve
Connector Terminal
B207 1 Ground Rear blower motor ON Battery voltage
OFF 0 V
Rear A/C sole noid valve
—Continuity
Connector Terminal
B207 2 Ground Existed
+ −Vol tag e
(Approx.)
Rear A/C relay
Connector Terminal
E87 1
Ground Battery voltage
3
Revision: 2010 May2011 QX56

REAR A/C SOLENOID VALVEHAC-129
< DTC/CIRCUIT DIAGNOSIS > [AUTOMATIC AIR CONDITIONING]
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NO >> Repair harness or connector between rear A/C relay and fuse block (J/B).
5.CHECK REAR A/C RERAY CONTROL CIRCUIT FOR OPEN
1. Turn ignition switch OFF.
2. Disconnect A/C auto amp. connector.
3. Check continuity between rear A/C relay har ness connector and A/C auto amp. harness connector.
Is the inspection result normal?
YES >> GO TO 6.
NO >> Repair harness or connector.
6.CHECK REAR A/C RELAY CONTROL CIRCUIT FOR SHORT
Check continuity between rear A/C relay harness connector and ground.
Is the inspection result normal?
YES >> GO TO 7.
NO >> Repair harness or connector.
7.CHECK REAR A/C SOLENOID VALVE POWER SUPPLY CIRCUIT
Check continuity between rear A/C relay harness c onnector and rear A/C solenoid valve harness connector.
Is the inspection result normal?
YES >> GO TO 8.
NO >> Repair harness or connector.
8.CHECK REAR A/C RELAY
Check rear A/C relay. Refer to HAC-129, "
Component Inspection".
Is the inspection result normal?
YES >> Replace A/C auto amp.. Refer to HAC-146, "Removal and Installation".
NO >> Replace rear A/C relay.
Component InspectionINFOID:0000000006275977
1.CHECK REAR A/C RELAY
1. Remove rear A/C relay.
Rear A/C relay A/C auto amp. Continuity
Connector Terminal Connector Terminal
E87 2 M50 38 Existed
Rear A/C relay —Continuity
Connector Terminal
E87 2 Ground Not existed
Rear A/C relay Rear A/C solenoid valve Continuity
Connector Terminal Connector Terminal
E87 5 B207 1 Existed
Revision: 2010 May2011 QX56

HAC-130
< DTC/CIRCUIT DIAGNOSIS >[AUTOMATIC AIR CONDITIONING]
REAR A/C SOLENOID VALVE
2. Check continuity between the r
ear A/C relay terminal 3 and 5
when the voltage is supplied between terminal 1 and 2.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace rear A/C relay.
Blower relay Voltage Continuity
Te r m i n a l
35 ON Existed
OFF Not existed
JSIIA1551ZZ
Revision: 2010 May2011 QX56

REAR BLOWER MOTORHAC-131
< DTC/CIRCUIT DIAGNOSIS > [AUTOMATIC AIR CONDITIONING]
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REAR BLOWER MOTOR
Diagnosis ProcedureINFOID:0000000006275978
1.CHECK FUSE
1. Turn ignition switch OFF.
2. Check 20A fuse [No. 16, 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 REAR BLOWER MOTOR POWER SUPPLY
1. Turn ignition switch OFF.
2. Disconnect rear blower motor connector.
3. Turn ignition switch ON.
4. Check voltage between rear blower motor harness connector and ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair harness or connector between rear blower motor and fuse block (J/B).
3.CHECK REAR BLOWER MOTOR GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Check continuity between rear blower motor harness connector and ground.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair harness or connector.
4.CHECK REAR BLOWER MOTOR CONTROL SIGNAL CIRCUIT
1. Disconnect A/C auto amp. connector.
2. Check continuity between rear blower motor harness connector and A/C auto amp. harness connector.
Is the inspection result normal?
YES >> GO TO 5.
NO >> Repair harness or connector.
5.CHECK REAR BLOWER MOTOR CONTROL SIGNAL
1. Reconnect rear blower motor connector and A/C auto amp. connector.
2. Turn ignition switch ON.
3. Operate MODE switch to set air outlet to VENT.
+
−Vol tag e
Rear blower motor
Connector Terminal M302 1 Ground Battery voltage
Rear blower motor —Continuity
Connector Terminal
M302 3 Ground Existed
Rear blower motor A/C auto amp. Continuity
Connector Terminal Connector Terminal
M302 2 M50 34 Existed
Revision: 2010 May2011 QX56

HAC-132
< DTC/CIRCUIT DIAGNOSIS >[AUTOMATIC AIR CONDITIONING]
REAR BLOWER MOTOR
4. Change fan speed from Lo to Hi, and check duty rati
os between rear blower motor harness connector and
ground by using an oscilloscope.
NOTE:
Calculate drive signal duty ratio as shown in the figure.
T2 = Approx. 1.6 ms
Is the inspection result normal?
YES >> Replace rear blower motor. Refer to VTL-16, "REAR A/C UNIT ASSEMBLY : Removal and Instal-
lation".
NO >> Replace A/C auto amp.. Refer to HAC-146, "
Removal and Installation".
Component InspectionINFOID:0000000006275979
1.CHECK REAR BLOWER MOTOR-I
1. Remove rear blower motor.
2. Check that there is not any mixing foreign object in the rear blower motor.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Replace rear blower motor. Refer to VTL-16, "
REAR A/C UNIT ASSEMBLY : Removal and Instal-
lation".
2.CHECK REAR BLOWER MOTOR-II
Check that there is not breakage or damage in the rear blower motor.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Replace rear blower motor. Refer to VTL-16, "
REAR A/C UNIT ASSEMBLY : Removal and Instal-
lation".
3.CHECK REAR BLOWER MOTOR-III
Check that rear blower motor turns smoothly.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace rear blower motor. Refer to VTL-16, "
REAR A/C UNIT ASSEMBLY : Removal and Instal-
lation".
Rear 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
Revision: 2010 May2011 QX56

FRONT AUTOMATIC AIR CONDITIONING SYSTEMHAC-133
< SYMPTOM DIAGNOSIS > [AUTOMATIC AIR CONDITIONING]
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SYMPTOM DIAGNOSIS
FRONT AUTOMATIC AIR CONDITIONING SYSTEM
Diagnosis Chart By SymptomINFOID:0000000006275980
NOTE:
Perform the self-diagnoses with CONSULT-III before per forming the symptom diagnosis. If DTC is detected,
perform the corresponding diagnosis.
Symptom Corresponding malfunction part Reference
 Front air conditioning system does not activate.
 Front air conditioning system cannot be con-
trolled.
 Operation status of front air conditioning system is
not indicated on front dis-
play. Fail-safe activates Multi AV system
AV- 1 9 9 , "
Symptom Table"
Fail-safe does not acti-
vate Power supply system of A/C auto
amp.
 A/C auto amp. HAC-110, "A/C AUTO AMP. : Diag-
nosis Procedure"
 Air outlet does not change (Except upper ventila-
tion).
 Front mode door motor does not operate normally.  Circuit between front mode door
motor and A/C auto amp.
 Front mode door motor control link-
age
 Front mode door motor
 A/C auto amp. HAC-112, "FRONT MODE DOOR
MOTOR : Diagnosis Procedure"
 Upper ventilator door does not change.
 Upper ventilator door motor does not operate nor-
mally.  Circuit between upper ventilator
door motor and A/C auto amp.
 Upper ventilator door motor installa- tion condition
 Upper ventilator door motor
 A/C auto amp. HAC-116, "UPPER VENTILATOR
DOOR MOTOR : Diagnosis Proce-
dure"
 Discharge air temperature of driver side does not
change.
 Front air mix door motor (driver side) does not op-
erate normally.  Circuit between front air mix door
motor (driver side ) and A/C auto
amp.
 Front air mix door motor (driver side)
installation condition
 Front air mix door motor (driver side)
 A/C auto amp. HAC-110, "FRONT AIR MIX DOOR
MOTOR (DRIVER SIDE) : Diagno-
sis Procedure"
 Discharge air temperature of passenger side does
not change.
 Front air mix door motor (passenger side) does not
operate normally.  Circuit between front air mix door
motor (passenger side) and A/C
auto amp.
 Front air mix door motor (passenger side) installation condition
 Front air mix door motor (passenger side)
 A/C auto amp. HAC-111, "FRONT AIR MIX DOOR
MOTOR (PASSENGER SIDE) : Di-
agnosis Procedure"
 Intake door does not change.
 Intake door motor does not operate normally.
 Circuit between intake door motor
and A/C auto amp.
 Intake door motor control linkage
 Intake door motor
 A/C auto amp. HAC-113, "INTAKE DOOR MOTOR
: Diagnosis Procedure"
All door motors do not operate normally.
 Each door motor power supply and
ground circuit
 A/C auto amp. HAC-118, "Diagnosis Procedure"
Front blower motor operation is malfunctioning.  Power supply system of front blower
motor
 Circuit between front blower motor and A/C auto amp..
 Front blower motor
 A/C auto amp. HAC-121, "Diagnosis Procedure"
Revision: 2010 May2011 QX56