2011 INFINITI QX56 reset

HAC-8
< SYSTEM DESCRIPTION >[AUTOMATIC AIR CONDITIONING]
COMPONENT PARTS
REAR AUTOMATIC AIR CONDITIONING SYSTEM
Heater & cooling unit
assemblyAspirator Refer to
HAC-12
.
Front air mix door motor (Driver
side) The LCU (Local Control Unit) is installe
d to front air mix door motor (driver
side) so as to perform the multiplex communication control (LIN).
Refer to HAC-18, "
FRONT AUTOMATIC AIR CONDITIONING SYSTEM :
Door Control".
Front air mix door motor (Pas-
senger side) The LCU (Local Control Unit) is installed to front air mix door motor (pas-
senger side) so as to perform the multiplex communication control (LIN).
Refer to
HAC-18, "
FRONT AUTOMATIC AIR CONDITIONING SYSTEM :
Door Control".
Front mode door motor The LCU (Local Control Unit) is installed to front mode door motor so as to
perform the multiplex communication control (LIN).
Refer to
HAC-18, "
FRONT AUTOMATIC AIR CONDITIONING SYSTEM :
Door Control".
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.
Upper ventilator door motor The LCU (Local Control Unit) is installed to upper ventilator door motor so
as to perform the multiplex communication control (LIN).
Refer to
HAC-18, "
FRONT AUTOMATIC AIR CONDITIONING SYSTEM :
Door Control".
IPDM E/R A/C relay is integrated in
IPDM E/R. IPDM E/R op erates A/C relay when A/
C compressor request signal is received from ECM via CAN communica-
tion line.
Magnet clutch The magnet clutch is the device that drives the compressor with the signal
from IPDM E/R. Compressor is driven by the magnet clutch which is mag-
netized by electric power supply. IPDM controls magnet clutch by turning
the built in A/C relay to ON
⇔ OFF according to ECM request.
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.
Refrigerant pressure sensor Refer to HAC-13
.
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..
Component Description
Revision: 2010 May2011 QX56

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
Revision: 2010 May2011 QX56

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..
Revision: 2010 May2011 QX56

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.
Revision: 2010 May2011 QX56

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
Revision: 2010 May2011 QX56

SYSTEMHAC-15
< SYSTEM DESCRIPTION > [AUTOMATIC AIR CONDITIONING]
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- HAC-17, "FRONT AUTOMATIC AIR CONDITIONING SYSTEM : Air Outlet Control"
-HAC-17, "FRONT AUTOMATIC AIR CONDITIONIN G SYSTEM : Compressor Control"
-HAC-18, "FRONT AUTOMATIC AIR CONDITION ING SYSTEM : Door Control"
-HAC-21, "FRONT AUTOMATIC AIR CONDITIONIN G SYSTEM : Temperature Control"
- Correction for input value of each sensor
Ambient sensor (setting temperature correction) A/C auto amp. controls passenger room temperature so that the optimum level always matches the temper-
ature level that passenger may feel. Correction is applied to the target temperature that is set using temper-
ature control dial, according to ambient temperature detected by ambient sensor.
Front in-vehicle sensor [in-vehicle temperature (front side) correction]
 Passenger room temperature (front side) detected by front in-vehicle sensor is corrected for each front air
conditioning control (driver side and passenger side)
Intake sensor (intake temperature correction)
 A/C auto amp. performs correction to change recognition intake temperature of A/C auto amp. quickly when
difference is large between recognition intake temperat ure and intake temperature detected by intake tem-
perature sensor. The correction is performed to change recognition intake temperature slowly when differ-
ence is small.
Sunload sensor (sunload amount correction) Sunload amount detected by sunload sensor is correc ted for each air conditioning control (driver side and
passenger side).
 A/C auto amp. performs correction to change recogni tion sunload amount of A/C auto amp. slowly when
sunload amount changes quickly, for exampl e when entering or exiting a tunnel.
Control by ECM
- Cooling fan control
Refer to EC-41, "
COOLING FAN CONTROL : System Description".
- Air conditioning cut control.
Refer to EC-47, "
AIR CONDITIONING CUT CONTRO L : System Description".
Control by IPDM E/R- Relay control
Refer to PCS-5, "
RELAY CONTROL SYSTEM : System Description".
- Cooling fan control
Refer to PCS-8, "
POWER CONTROL SYSTEM : System Description".
 Front A/C control (preset switch) transmits the co mmands for front automatic air conditioning system opera-
tion to AV control unit via communication line, then AV control unit transmits the commands to A/C auto amp.
via CAN communication. A/C auto amp. transmits each indication information to AV control unit via CAN
communication. AV control unit displays each indication information that is received.
FRONT AUTOMATIC AIR CONDITIONIN G SYSTEM : Air Flow ControlINFOID:0000000006275862
DESCRIPTION
 A/C auto amp. changes duty ratio of blower motor dr ive signal and controls air flow continuously. When air
flow is increased, duty ratio of front blower moto r control signal gradually increases to prevent a sudden
increase in air flow.
 In addition to manual control and automatic control, air flow control is consist of starting fan speed control,
low coolant temperature starting control, high in-vehi cle temperature starting control and fan speed control at
door motor operation
AUTOMATIC AIR FLOW CONTROL
 A/C auto amp. decides target air flow depending on target front air mix door opening angle.
 A/C auto amp. changes duty ratio of front blower moto r control signal and controls the air flow continuously
so that air flow matches to target air flow.
Revision: 2010 May2011 QX56

HAC-22
< SYSTEM DESCRIPTION >[AUTOMATIC AIR CONDITIONING]
SYSTEM
If a communication error exists between the A/C auto
amp., and the AV control unit and preset switch for 30
seconds or longer, air conditioning is controlled under the following conditions:
When ambient temperature is less than 3 °C (37 °F) and engine coolant tem perature is less than 56°C (133 °F)
When ambient temperature is 3 °C (37 °F) or more, or engine coolant temperature is 56 °C (133 °F) or more
REAR AUTOMATIC AIR CONDITIONING SYSTEM
Compressor : ON
Air outlet : DEF
Air inlet : FRE (Fresh air intake)
Blower fan speed : AUTO
Set temperature : Setting before communication error occurs
Compressor : ON
Air outlet : AUTO
Air inlet : 20% FRE (20% fresh air intake)
Blower fan speed : AUTO
Set temperature : Setting before communication error occurs
Revision: 2010 May2011 QX56

HAC-24
< SYSTEM DESCRIPTION >[AUTOMATIC AIR CONDITIONING]
SYSTEM
 A/C auto amp. controls passenger r
oom temperature so that the optimum level always matches the temper-
ature level that passenger may feel. Correction is applied to the target temperature that is set using temper-
ature control dial, according to ambient temperature detected by ambient sensor.
Rear in-vehicle sensor [in-vehicle temperature (rear side) correction]
 Passenger room temperature (rear side) detected by r ear in-vehicle sensor is corrected for each rear auto-
matic air conditioning control.
Intake sensor (intake temperature correction)
 A/C auto amp. performs correction to change recogniti on intake temperature of A/C auto amp. quickly when
difference is large between recognition intake temperat ure and intake temperature detected by intake tem-
perature sensor. The correction is performed to change recognition intake temperature slowly when differ-
ence is small.
Sunload sensor (sunload amount correction) Sunload amount detected by sunload sensor is correct ed for each rear automatic air conditioning control.
 A/C auto amp. performs correction to change recogni tion sunload amount of A/C auto amp. slowly when
sunload amount changes quickly, for exampl e when entering or exiting a tunnel.
 Front control
Operation by front controller
- Front A/C control (preset switch) transmits the co mmands for rear automatic air conditioning system opera-
tion to AV control unit via communication line, then AV control unit transmits the commands to A/C auto amp.
via CAN communication. A/C auto amp. transmits each indication information to AV control unit via CAN
communication. AV control unit displays each indication information that is received.
Operation by rear controller- Rear A/C control transmits the commands for rear automatic air conditioning system operation to A/C auto
amp. via communication line.
REAR AUTOMATIC AIR CONDITIONIN G SYSTEM : Air Flow ControlINFOID:0000000006275871
DESCRIPTION
 A/C auto amp. changes duty ratio of blower motor dr ive signal and controls air flow continuously. When air
flow is increased, duty ratio of rear blower moto r control signal gradually increases to prevent a sudden
increase in air flow.
 In addition to manual control and automatic control, air flow control is compose of starting fan speed control,
low coolant temperature starting control, high in-vehi cle temperature starting control and fan speed control at
door motor operation
AUTOMATIC AIR FLOW CONTROL
 A/C auto amp. decides target air flow depending on target rear air mix door opening angle.
 A/C auto amp. changes duty ratio of rear blower moto r control signal and controls the air flow continuously
so that air flow matches to target air flow.
 When air outlet is VENT or B/L, the minimum air flow is changed depending on sunload.
STARTING AIR FLOW CONTROL
JMIIA0738GB
Revision: 2010 May2011 QX56