heater INFINITI QX56 2011 Factory Workshop Manual
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COMPONENT PARTSHAC-9
< SYSTEM DESCRIPTION > [AUTOMATIC AIR CONDITIONING]
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REAR AUTOMATIC AIR CONDITIONING SY STEM : Component Parts Location
INFOID:0000000006275850
1. Rear A/C control 2. Preset switch 3. Engine coolant temperature sensor
Refer to EC-16, "
Component Parts
Location".
4. ECM Refer to EC-16, "
Component Parts
Location". 5. Ambient sensor 6. AV control unit
Refer to AV- 9 , "
Component Parts Lo-
cation".
7. Combination meter Refer to MWI-6, "
METER SYSTEM :
Component Parts Location". 8. Sunload sensor 9. Front display
10. Rear mode door motor 11. Rear air mix door motor 12. Rear in-vehicle sensor
13. Rear blower motor 14. Rear A/C solenoid valve 15. Rear A/C relay
16. Intake sensor 17. A/C auto amp.
A. Right side of rear A/C unit assembly B. Left side of rear A/C unit assembly C. Back side of engine room (RH)
D. Left side of heater & cooling unit as- sembly E. Cluster lid C is removed
JMIIA0813ZZ
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HAC-10
< SYSTEM DESCRIPTION >[AUTOMATIC AIR CONDITIONING]
COMPONENT PARTS
REAR AUTOMATIC AIR CONDITIONING SYSTEM : Component Description
INFOID:0000000006275851
ACCS (ADVANCED CLIMATE CONTROL SYSTEM)
Component Description
Ambient sensor Ambient sensor measures ambient air temperature. The sensor uses a
thermistor which is sensitive to the change in temperature. The electrical
resistance of the thermistor decreases as temperature increases.
AV c o n t r o l u n i t AV control unit transmits front A/C control operation signal to A/C auto amp.
via CAN communication line.
A/C auto amp. A/C auto amp. controls rear automatic air conditioning system by inputting
and calculating signals from each sensor and each switch. A/C auto amp.
has self-diagnosis function. Diagnosis of rear automatic air conditioning
system can be performed quickly.
Combination meter Combination meter transmits vehicle speed signal to A/C auto amp. via
CAN communication line.
ECM ECM transmits engine coolant temperature signal to A/C auto amp. via
CAN communication line.
Engine coolant temperature sensor Engine coolant temperature sensor measures engine coolant temperature.
The sensor uses a thermistor which is sensitive to the change in tempera-
ture. The electrical resistance of the thermistor decreases as temperature
increases.
Front display Front display indicates operation status of rear automatic air conditioning
system.
Heater & cooling unit
assembly Intake sensor Intake sensor measures temperature of front evaporator fin temperature.
The sensor uses a thermistor which is sensitive to the change in tempera-
ture. The electrical resistance of the thermistor decreases as temperature
increases.
Preset switch Preset switch is integrated with front A/C control and AV operation switch.
Front A/C control operation signal is transmitted from preset switch to AV
control unit via communication line.
Rear A/C control The operation of the rear A/C control is communicated with the A/C auto
amp. via communication line.
Rear A/C relay Power is supplied to the rear A/C solenoid valve through rear A/C relay with
A/C auto amp. control.
Rear A/C unit assem-
bly Rear air mix door motor
The LCU (Local Contro
l Unit) is installed to rear air mix door motor so as to
perform the multiplex communication control (LIN).
Refer to HAC-26, "
REAR AUTOMATIC AIR CONDITIONING SYSTEM :
Door Control".
Rear A/C solenoid valve Rear A/C solenoid valve operates by power supply from rear A/C relay and
opens refrigerant line to rear evaporator.
Rear blower motor Refer to HAC-13
.
Rear in-vehicle sensor Rear in-vehicle sensor measures temperature of intake air that flows
through rear blower motor to passenger room. The sensor uses a ther-
mistor which is sensitive to the change in temperature. The electrical resis-
tance of the thermistor decreases as temperature increases.
Rear mode door motor The LCU (Local Control Unit) is installed to rear mode door motor so as to
perform the multiplex communication control (LIN).
Refer to
HAC-26, "
REAR AUTOMATIC AIR CONDITIONING SYSTEM :
Door Control".
Sunload sensor Sunload sensor measures sunload amount. This sensor is a dual system
so that sunload for driver side and passenger side are measured separate-
ly. This sensor converts sunload amount to voltage signal by photodiode
and transmits to A/C auto amp..
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COMPONENT PARTSHAC-11
< SYSTEM DESCRIPTION > [AUTOMATIC AIR CONDITIONING]
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ACCS (ADVANCED CLIMATE CONTROL SYSTEM) : Component Parts Location
INFOID:0000000006275852
ACCS (ADVANCED CLIMATE CONTRO L SYSTEM) : Component Description
INFOID:0000000006275853
1. Preset switch 2. Exhaust gas / outside odor detecting
sensor3. AV control unit
Refer to AV- 9 , "
Component Parts Lo-
cation".
4. Front display 5. Ionizer 6. Intake door motor
7. A/C auto amp.
A. Left side of heater & cooling unit as- sembly B. Back side of blower unit assembly C. Cluster lid C is removed
JMIIA0814ZZ
Component Description
Blower unit Intake door motor The LCU (Local Control Unit) is installed to intake door motor so as to per-
form the multiplex communication control (LIN).
Refer to
HAC-18, "
FRONT AUTOMATIC AIR CONDITIONING SYSTEM :
Door Control".
AV c o n t r o l u n i t AV control unit transmits A/C switch operation signal to A/C auto amp. via
CAN communication line.
A/C auto amp. A/C auto amp. controls ACCS (advanced climate control system) by input-
ting and calculating signals from each sensor and each switch. A/C auto
amp. has self-diagnosis function. Diagnosis of ACCS (advanced climate
control system) can be performed quickly.
Exhaust gas / outside odor detecting sensor Exhaust gas / outside odor detecting sensor measures unpleasant odor out-
side of passenger room. In addition to previous exhaust gas detection func-
tion, unpleasant odor in ambient atmosphere is measured.
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HAC-12
< SYSTEM DESCRIPTION >[AUTOMATIC AIR CONDITIONING]
COMPONENT PARTS
Aspirator
INFOID:0000000006275856
The aspirator generates the vacuum by the air blown from the heater
& cooling unit and draws the air of the passenger room to the front
in-vehicle sensor area via the aspirator duct.
Front Blower MotorINFOID:0000000006275857
The front blower motor utilizes a brush-less motor with a rotating
magnet. Quietness is improved comparing to a conventional motor
(brush motor) that rotates coil while brush functions as contact
points.
Front display Front display indicates operation status of ACCS (advanced climate control
system).
Heater & cooling unit as-
sembly Ionizer Ionizer generates an approximately equal proportional amount of positive
and negative ions in the air.
Preset switch Preset switch is integrated with front A/C control and AV operation switch.
Front A/C control operation signal is transmitted from preset switch to AV
control unit via communication line.
Component Description
RJIA1804E
RJIA2467J
ZHA152H
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SYSTEMHAC-19
< SYSTEM DESCRIPTION > [AUTOMATIC AIR CONDITIONING]
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*: Inlet status is displayed by indi cator when activating automatic control
Without ACCS (Advanced Climate Control System)
1. Intake door 2. In-cabin microfilter 3. Blower motor
4. Evaporator 5. Air mix door (Driver side/Passenger
side)6. Heater core
7. Foot door 8. Ventilator door 9. Upper ventilator door
10. Defroster door Fresh air intake Recirculation air
Center ventilator Side ventilator Upper ventilator
Foot Rear foot Defroster
Switch/Dial position Door position
Ventilator door Foot
doorDefroster
door Intake
door Upper
ventilator
door Air mix
door
(Driver side) Air mix
door
(Passen-
ger
side)
AUTO switch AUTO — AUTO
MODE switch VENT H E N —
B/L I F N —
FOOT J G O — D/F J G O B —
DEF switch J E P B K —
Intake switch
*FRE — B —
REC — A —
Upper ventila- tor switch ON — L – M —
OFF — K —
Temperature control dial
(Driver side) DUAL
switch:
OFF18.0
°C (60 °F) — C
18.5 °C (61 °F) ⇔
31.5 °C (89 °F) —AUTO
32.0 °C (90 °F) — D
Temperature control dial
(Driver side) DUAL
switch:
ON18.0
°C (60 °F) — C —
18.5 °C (61 °F) ⇔
31.5 °C (89 °F) —AUTO—
32.0 °C (90 °F) — D —
Temperature control dial
(Passenger side) 18.0
°C (60 °F) — C
18.5 °C (61 °F) ⇔
31.5 °C (89 °F) —AUTO
32.0 °C (90 °F) — D
OFF switch AUTO —
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HAC-20
< SYSTEM DESCRIPTION >[AUTOMATIC AIR CONDITIONING]
SYSTEM
1. Intake door 2. In-cabin microfilter 3. Blower motor
4. Evaporator 5. Air mix door (Driver side/Passenger
side)6. Heater core
7. Foot door 8. Ventilator door 9. Upper ventilator door
10. Defroster door Fresh air intake Recirculation air
Center ventilator Side ventilator Upper ventilator
Foot Rear foot Defroster
JMIIA0727ZZ
Switch/Dial position Door position
Ventilator door Foot
doorDefroster
door Intake
door Upper
ventilator door Air mix
door
(Driver side) Air mix
door
(Passen- ger
side)
AUTO switch AUTO — AUTO
MODE switch VENT H E N —
B/L I F N —
FOOT J G O — D/F J G O B —
DEF switch J EPBK —
FRE switch
*—B—
REC switch
*—A—
Upper ventila- tor switch ON — L – M —
OFF — K —
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HAC-26
< SYSTEM DESCRIPTION >[AUTOMATIC AIR CONDITIONING]
SYSTEM
REAR AUTOMATIC AIR CONDITION ING SYSTEM : Door Control
INFOID:0000000006275873
DOOR MOTOR CONTROL
LCU (Local Control Unit) is built in to each door moto r. And detects door position by PBR (Potentio Balance
Resistor).
A/C auto amp. communicates with each LCU via comm unication line. And receives each door position feed
back signal from each LCU.
Each LCU controls each door to the appropriate pos ition depending on the control signal from A/C auto amp.
when the door movement is complete, transmits the signal of door movement completion to A/C auto amp.
SWITCHES AND THEIR CONTROL FUNCTION
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1. Rear blower motor 2. Rear evaporator 3. Rear air mix door
4. Rear heater core 5. Rear mode door
Recirculation air
Rear ventilator Rear A/C foot
Switch/Dial position Door position
Rear mode door Rear air mix door
AUTO switch Front A/C control
AUTO
Rear A/C control
JMIIA0744ZZ
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HAC-134
< SYMPTOM DIAGNOSIS >[AUTOMATIC AIR CONDITIONING]
FRONT AUTOMATIC AIR CONDITIONING SYSTEM
Compressor does not operate. Circuit between magnet clutch and
IPDM E/R
Magnet clutch
IPDM E/R (A/C relay)
Circuit between ECM and refriger- ant pressure sensor
Refrigerant pressure sensor
CAN communication circuit
A/C auto amp. HAC-142, "Diagnosis Procedure"
Insufficient cooling.
No cool air comes out. (Air flow volume is normal.)
Magnet clutch control system
Drive belt slipping
Refrigerant cycle
Air leakage from each duct
A/C auto amp. connection recogni-
tion signal circuit
Temperature settin g trimmer (front)HAC-138, "FRONT AIR CONDI-
TIONER : Diagnosis Procedure"
Insufficient heating.
No warm air comes out. (Air flow volume is nor-
mal.) Engine cooling system
Heater hose
Heater core
Air leakage from each duct
Temperature settin
g trimmer (front)HAC-140, "FRONT AIR CONDI-
TIONER : Diagnosis Procedure"
Noise is heard when front
air conditioning system op-
erates. During compressor
operation
Refrigerant cycle
HA-27, "
Symptom Table"
During front blower
motor operation Mixing any foreign object in front
blower motor
Front blower motor fan breakage
Front blower motor rotation inferiori- ty HAC-122, "Component Inspection
(Front Blower Motor)"
Memory function does not operate.
Setting temperature is not memorized.
Battery power supply system of A/C
auto amp.
A/C auto amp. HAC-110, "A/C AUTO AMP. : Diag-
nosis Procedure"
Symptom Corresponding malfunction part Reference
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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
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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