INFINITI QX56 2011 Factory Service Manual

REAR AUTOMATIC AIR CONDITIONING SYSTEMHAC-135
< SYMPTOM DIAGNOSIS > [AUTOMATIC AIR CONDITIONING]
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REAR AUTOMATIC AIR CONDITIONING SYSTEM
Diagnosis Chart By SymptomINFOID:0000000006275981
NOTE:
 Perform the self-diagnoses with CONSULT-III before performing the symptom diagnosis. If DTC is detected,
perform the corresponding diagnosis.
 The following table is based on the condition that fr ont automatic air conditioning system operates normally.
Symptom Corresponding malfunction part Reference
 Rear air conditioning system cannot be controlled. (Front A/C control)
 Operation status of rear air conditioning system is not indicated on front display. Multi AV system
AV- 1 9 9 , "
Symptom Table"
Rear air conditioning sys-
tem cannot be controlled.
(Rear A/C control)Operation status of
rear air conditioning
system is not indicated
on rear A/C control
display
 Power supply system of rear A/C
control
 Rear A/C control HAC-115, "
REAR A/C CONTROL :
Diagnosis Procedure"
Operation status of
rear air conditioning
system is indicated on
rear A/C control dis-
play Communication circuit between rear
A/C control and A/C auto amp.
 A/C auto amp. HAC-127, "
Diagnosis Procedure"
 Air outlet does not change.
 Rear mode door motor does not operate normally.  Circuit between rear mode door mo-
tor and A/C auto amp.
 Rear mode door motor control link- age
 Front mode door motor
 A/C auto amp. HAC-116, "REAR MODE DOOR
MOTOR : Diagnosis Procedure"
 Discharge air temperature does not change.
 Rear air mix door motor does not operate normally.  Circuit between rear air mix door
motor and A/C auto amp.
 Rear air mix door motor installation condition
 Rear air mix door motor
 A/C auto amp. HAC-114, "REAR AIR MIX DOOR
MOTOR : Diagnosis Procedure"
Rear blower motor operation is malfunctioning.
 Power supply system of rear blower
motor
 Circuit between rear blower motor
and A/C auto amp..
 Rear blower motor
 A/C auto amp. HAC-131, "Diagnosis Procedure"
 Insufficient cooling.
 No cool air comes out. (Air flow volume is normal.)  Power supply system of rear A/C re-
lay
 Circuit between rear A/C relay and A/C auto amp..
 Circuit between rear A/C relay and rear A/C solenoid valve.
 Circuit between rear A/C solenoid
valve and ground.
 Rear A/C relay
 Rear A/C solenoid valve
 A/C auto amp.
 Refrigerant cycle
 Air leakage from each duct
 Temperature setti ng trimmer (rear) HAC-139, "REAR AIR CONDI-
TIONER : Diagnosis Procedure"
Revision: 2010 May2011 QX56

HAC-136
< SYMPTOM DIAGNOSIS >[AUTOMATIC AIR CONDITIONING]
REAR AUTOMATIC AIR CONDITIONING SYSTEM
 Insufficient heating.
 No warm air comes out. (Air flow volume is nor-
mal.)  Engine cooling system
 Heater hose
 Rear heater core
 Air leakage from each duct
 Temperature setting trimmer (rear)
HAC-141, "REAR AIR CONDI-
TIONER : Diagnosis Procedure"
Noise is heard when rear blower motor operates.
 Mixing any foreign object in rear
blower motor
 Rear blower motor fan breakage
 Rear blower motor rotation inferiori- ty HAC-132, "Component Inspection"
Symptom Corresponding malfunction part Reference
Revision: 2010 May2011 QX56

ACCS (ADVANCE CLIMATE CONTROL SYSTEM)HAC-137
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ACCS (ADVANCE CLIMATE CONTROL SYSTEM)
Symptom TableINFOID:0000000006275982
NOTE:
 Perform the self-diagnoses with CONSULT-III before performing the symptom diagnosis. If DTC is detected,
perform the corresponding diagnosis.
 The following table is based on the condition that fr ont automatic air conditioning system operates normally.
Symptom Corresponding malfunction part Reference
Auto intake switch cannot be operated. [Automatic
intake control (exhaust gas / outside odor detecting
mechanism) does not operate] Multi AV system
AV- 1 9 9 , "
Symptom Table"
Plasmacluster™ control does not operate.
NOTE:
 Plasmacluster
™ ion technology developed by
Sharp Corporation is installed in this item.
 Plasmacluster
™ is a trademark of Sharp Corpora-
tion.  Power supply system of ionizer
 The circuit between ionizer and A/C
auto amp.
 Ionizer
 A/C auto amp. HAC-124, "
Diagnosis Procedure"
Operation status of Plasmacluster™ control does not
switch according to air flow.
NOTE:
 Plasmacluster
™ ion technology developed by
Sharp Corporation is installed in this item.
 Plasmacluster
™ is a trademark of Sharp Corpora-
tion. A/C auto amp.
Replace A/C auto amp.. Refer to
HAC-146, "
Removal and Installa-
tion".
Revision: 2010 May2011 QX56

HAC-138
< SYMPTOM DIAGNOSIS >[AUTOMATIC AIR CONDITIONING]
INSUFFICIENT COOLING
INSUFFICIENT COOLING
FRONT AIR CONDITIONER
FRONT AIR CONDITIONER : DescriptionINFOID:0000000006275984
Symptom Insufficient cooling
 No cool air comes out. (Air flow volume is normal.)
FRONT AIR CONDITIONER
: Diagnosis ProcedureINFOID:0000000006275985
NOTE:
Perform self-diagnoses with CONSULT-III before perform ing symptom diagnosis. If any DTC is detected, per-
form the corresponding diagnosis.
1.CHECK MAGNET CLUTCH OPERATION
1. Turn ignition switch ON.
2. Operate fan switch.
3. Press A/C switch.
4. Check that A/C indicator turns ON. Check visually and by sound that compressor operates.
5. Press A/C switch again.
6. Check that A/C indicator turns OFF. Check that compressor stops.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Perform diagnosis of “COMPRESSOR DOSE NOT OPERATE” in “SYMPTOM DIAGNOSIS”.
Refer to HAC-142, "
Diagnosis Procedure".
2.CHECK DRIVE BELT
Check tension of drive belt. Refer to EM-20, "
Checking".
Is the inspection result normal?
YES >> GO TO 3.
NO >> Adjust or replace drive belt depending on the inspection results.
3.CHECK REFRIGERANT CYCLE
Connect recovery/recycling recharging equipment to the vehicle and perform pressure inspection with gauge.
Refer to HA-27, "
Symptom Table".
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair or replace parts depending on the inspection results.
4.CHECK AIR LEAKAGE FROM EACH DUCT
Check duct and nozzle, etc. of the fr ont air conditioning system for leakage.
Is the inspection result normal?
YES >> GO TO 5.
NO >> Repair or replace parts depending on the inspection results.
5.CHECK AMBIENT TEMPERATURE DISPLAY
Check that there is not much diference between act ual ambient temperature and indicated temperature on
information display in combination meter.
Is the inspection result normal?
YES >> GO TO 6.
NO >> Perform diagnosis for the A/C auto amp. connection recognition signal circuit. Refer to MWI-74,
"DiagnosisProcedure".
6.CHECK SETTING OF TEMPERATURE SETTING TRIMMER (FRONT)
1. Check setting value of temperature setting trimmer (front). Refer to HAC-68, "
FRONT AUTOMATIC AIR
CONDITIONING SYSTEM : Temperature Setting Trimmer (Front)".
2. Check that temperature setting trimme r (front) is set to “+ direction”.
Revision: 2010 May2011 QX56

INSUFFICIENT COOLINGHAC-139
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NOTE:
The control temperature can be set with the setti ng of the temperature setting trimmer (front).
3. Set difference between set temperature and control temperature to “0”.
Is inspection result normal?
YES >> INSPECTION END
NO >> Replace A/C auto amp.. Refer to HAC-146, "
Removal and Installation".
REAR AIR CONDITIONER
REAR AIR CONDITIONER : DescriptionINFOID:0000000006275986
Symptom Insufficient cooling
 No cool air comes out. (Air flow volume is normal.)
REAR AIR CONDITIONER : Diagnosis ProcedureINFOID:0000000006275987
NOTE:
Perform self-diagnoses with CONSULT-III before performi ng symptom diagnosis. If any DTC is detected, per-
form the corresponding diagnosis.
1.CHECK REAR A/C SOLENOID VALVE
Check rear A/C solenoid valve. Refer to HAC-128, "
Diagnosis Procedure".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair or replace malfunctioning parts.
2.CHECK REFRIGERANT CYCLE
Connect recovery/recycling recharging equipment to t he vehicle and perform pressure inspection with gauge.
Refer to HA-27, "
Symptom Table".
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair or replace parts depending on the inspection results.
3.CHECK AIR LEAKAGE FROM EACH DUCT
Check duct and nozzle, etc. of the rear air conditioning system for leakage.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair or replace parts depending on the inspection results.
4.CHECK SETTING OF TEMPERATURE SETTING TRIMMER (REAR)
1. Check setting value of temperature setting trimmer (rear). Refer to HAC-69, "
REAR AUTOMATIC AIR
CONDITIONING SYSTEM : Temperature Setting Trimmer (Rear)".
2. Check that temperature setting trimmer (rear) is set to “+ direction”. NOTE:
The control temperature can be set with the sett ing of the temperature setting trimmer (rear).
3. Set difference between set temperature and control temperature to “0”.
Is inspection result normal?
YES >> INSPECTION END
NO >> Replace A/C auto amp.. Refer to HAC-146, "
Removal and Installation".
Revision: 2010 May2011 QX56

HAC-140
< SYMPTOM DIAGNOSIS >[AUTOMATIC AIR CONDITIONING]
INSUFFICIENT HEATING
INSUFFICIENT HEATING
FRONT AIR CONDITIONER
FRONT AIR CONDITIONER : DescriptionINFOID:0000000006275990
Symptom Insufficient heating
 No warm air comes out. (Air flow volume is normal.)
FRONT AIR CONDITIONER
: Diagnosis ProcedureINFOID:0000000006275991
NOTE:
Perform self-diagnoses with on board diagnosis and CO NSULT-III before performing symptom diagnosis. If
DTC is detected, perform the corresponding diagnosis.
1.CHECK COOLING SYSTEM
1. Check engine coolant level and check leakage. Refer to CO-8, "
Inspection".
2. Check reservoir tank cap. Refer to CO-11, "
RESERVOIR TANK CAP : Inspection".
3. Check water flow sounds of the engine coolant. Refer to CO-9, "
Refilling".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Refill engine coolant and repair or repl ace parts depending on the inspection results.
2.CHECK HEATER HOSE
Check installation of heater hose by visually or touching.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair or replace parts depending on the inspection results.
3.CHECK FRONT HEATER CORE
1. Check temperature of inlet hose and outlet hose of front heater core.
2. Check that inlet side of front heater core is hot and t he outlet side is slightly lower than/almost equal to the
inlet side.
CAUTION:
Always perform the temperature in spection in a short period of time because the engine coolant
temperature is very hot.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Replace front heater core. Refer to HA-44, "
HEATER CORE : Removal and Installation".
4.CHECK AIR LEAKAGE FROM EACH DUCT
Check duct and nozzle, etc. of front air conditioning system for air leakage.
Is the inspection result normal?
YES >> GO TO 5.
NO >> Repair or replace parts depending on the inspection results.
5.CHECK SETTING OF TEMPERATURE SETTING TRIMMER (FRONT)
1. Check setting value of temperature setting trimmer (front). Refer to HAC-68, "
FRONT AUTOMATIC AIR
CONDITIONING SYSTEM : Temperature Setting Trimmer (Front)".
2. Check that temperature setting trimmer (front) is set to “ − direction”.
NOTE:
The control temperature can be set by t he temperature setting trimmer (front).
3. Set difference between the set temperature and control temperature to “0”.
Are the symptoms solved?
YES >> INSPECTION END
NO >> Replace A/C auto amp.. Refer to HAC-146, "
Removal and Installation".
REAR AIR CONDITIONER
Revision: 2010 May2011 QX56

INSUFFICIENT HEATINGHAC-141
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REAR AIR CONDITIONER : DescriptionINFOID:0000000006275992
Symptom
 Insufficient heating
 No warm air comes out. (Air flow volume is normal.)
REAR AIR CONDITIONER : Diagnosis ProcedureINFOID:0000000006275993
CAUTION:
Perform the self-diagnoses with on board diagnosi s and CONSULT-III before performing symptom
diagnosis. If any malfunction result or DTC is detected, perform the corresponding diagnosis.
1.CHECK COOLING SYSTEM
1. Check engine coolant level and check leakage. Refer to CO-8, "
Inspection".
2. Check reservoir tank cap. Refer to CO-11, "
RESERVOIR TANK CAP : Inspection".
3. Check water flow sounds of the engine coolant. Refer to CO-9, "
Refilling".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Refill the engine coolant and repair or replace the parts depending on the inspection results.
2.CHECK HEATER HOSE
Check installation of heater hose by visually or touching.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair or replace parts depending on the inspection results.
3.CHECK REAR HEATER CORE
1. Check temperature of inlet hose and outlet hose of rear heater core.
2. Check that the inlet side of rear heater core is hot and the outlet side is slightly lower than/almost equal to
the inlet side.
CAUTION:
Always perform the temperature inspection in a sh ort period of time because the engine coolant
temperature is very hot.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Replace rear heater core. Refer to HA-48, "
HEATER CORE : Removal and Installation".
4.CHECK AIR LEAKAGE FROM EACH DUCT
Check duct and nozzle, etc. of the rear air conditioning system for air leakage.
Is the inspection result normal?
YES >> GO TO 5.
NO >> Repair or replace parts depending on the inspection results.
5.CHECK SETTING OF TEMPERATURE SETTING TRIMMER (REAR)
1. Check setting value of temperature setting trimmer (rear). Refer to HAC-69, "
REAR AUTOMATIC AIR
CONDITIONING SYSTEM : Temperature Setting Trimmer (Rear)".
2. Check that the temperature setting trimmer is set to “ − direction”.
NOTE:
The control temperature can be set by the temperature setting trimmer (rear).
3. Set the difference between the set temperature (rear) and control temperature to “0”.
Are the symptoms solved?
YES >> INSPECTION END
NO >> Replace A/C auto amp.. Refer to HAC-146, "
Removal and Installation".
Revision: 2010 May2011 QX56

HAC-142
< SYMPTOM DIAGNOSIS >[AUTOMATIC AIR CONDITIONING]
COMPRESSOR DOSE DOT OPERATE
COMPRESSOR DOSE DOT OPERATE
DescriptionINFOID:0000000006275994
Symptom: Compressor dose not operate.
Diagnosis ProcedureINFOID:0000000006275995
NOTE:
 Perform self-diagnoses with CONSULT-III before perfo
rming symptom diagnosis. If DTC is detected, per-
form the corresponding diagnosis.
 Check that refrigerant is enclosed in cooler cycle normally. If refrigerant amount is shortage from proper
amount, perform inspection of refrigerant leakage.
1.CHECK MAGNET CLUTCH OPERATION
Check magnet clutch. Refer to HAC-126, "
Component Function Check".
Does it operate normally?
YES >> GO TO 2.
NO >> Repair or replace malfunctioning parts.
2.CHECK REFRIGERANT PRESSURE SENSOR
Check refrigerant pressure sensor. Refer to EC-520, "
Component Function Check".
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair or replace malfunctioning parts.
3.CHECK A/C AUTO AMP. OUTPUT SIGNAL
With CONSULT-III
Check “COMP REQ SIG” and “FAN REQ SIG” in “DAT A MONITOR” mode of “HVAC” using CONSULT-III.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Replace A/C auto amp.. Refer to HAC-146, "
Removal and Installation".
4.CHECK ECM INPUT SIGNAL
With CONSULT-III
Check “AIR COND SIG” and “HEATER FAN SW” in “D ATA MONITOR” mode of “ECM” using CONSULT-III.
Is the inspection result normal?
YES >> GO TO 5.
NO >> Check CAN communication system. Refer to LAN-18, "
Trouble Diagnosis Flow Chart".
5.CHECK IPDM E/R INPUT SIGNAL
With CONSULT-III
1. Start engine.
Monitor item Condition Status
COMP REQ SIG A/C switch ON On
OFF Off
FAN REQ SIG Front blower motor ON On
OFF Off
Monitor item Condition Status
COMP REQ SIG A/C switch ON On
OFF Off
HEATER FAN SW Front blower motor ON On
OFF Off
Revision: 2010 May2011 QX56

COMPRESSOR DOSE DOT OPERATEHAC-143
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2. Check “AC COMP REQ” in “DATA MONITOR” mode of “IPDM E/R” using CONSULT-III.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Check CAN communication system. Refer to LAN-18, "
Trouble Diagnosis Flow Chart".
Monitor item Condition Status
AC COMP REQ A/C switch ON On
OFF Off
Revision: 2010 May2011 QX56

HAC-144
< REMOVAL AND INSTALLATION >[AUTOMATIC AIR CONDITIONING]
FRONT A/C CONTROL
REMOVAL AND INSTALLATION
FRONT A/C CONTROL
Removal and InstallationINFOID:0000000006275996
REMOVAL
1. Remove cluster lid C. Refer to
IP-14, "Removal and Installation".
2. Remove preset switch. Refer to AV-227, "
Removal and Installation".
3. Disconnect harness connector from front A/C control.
INSTALLATION
Install in the reverse order of removal.
Revision: 2010 May2011 QX56