door INFINITI QX56 2011 Factory Service Manual
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SYSTEMHAC-21
< SYSTEM DESCRIPTION > [AUTOMATIC AIR CONDITIONING]
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*: Inlet status is displayed by indi cator when activating automatic control
AIR DISTRIBUTION
FRONT AUTOMATIC AIR CONDITIONIN G SYSTEM : Temperature Control
INFOID:0000000006275867
When ignition switch is in the ON position, A/C auto amp. always
automatically controls temperatur e regardless of front air condi-
tioning operational state.
A/C auto amp. calculates the target front air mix door opening angle depending on set temperature, in-vehicle temperature (front
side), ambient temperature, and sunload.
Front air mix door is controlled depending on the comparison of current front air mix door opening angle and target front air mix
door opening angle.
Regardless of in-vehicle temperature (front side), ambient temper- ature, and sunload, front air mix door is fixed at the fully cold posi-
tion when set temperature is 18.0 °C (60 °F), and at the fully hot
position when set temperature is 32.0 °C (90 °F).
FRONT AUTOMATIC AIR CONDITI ONING SYSTEM : Fail-safeINFOID:0000000006275868
FAIL-SAFE FUNCTION
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 —
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)
Discharge air flow
Mode position Condition Air outlet/distribution
VENT FOOT DEF
Center Side Front Rear
DUAL and Up-
per ventilator
switch: OFF 50% 50% — — —
30% 30% 26% 14% —
— 14% 36% 23% 27%
— 12% 32% 20% 36%
—11%——89%
JMIIA0731GB
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SYSTEMHAC-23
< SYSTEM DESCRIPTION > [AUTOMATIC AIR CONDITIONING]
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REAR AUTOMATIC AIR CONDITION ING SYSTEM : System DiagramINFOID:0000000006275869
REAR AUTOMATIC AIR CONDITIONING SYSTEM : System DescriptionINFOID:0000000006275870
Rear automatic air conditioning system is c ontrolled by each function of A/C auto amp..
Control by A/C auto amp.-HAC-24, "REAR AUTOMATIC AIR CONDITIONIN G SYSTEM : Air Flow Control"
-HAC-25, "REAR AUTOMATIC AIR CONDITIONING SYSTEM : Air Outlet Control"
-HAC-26, "REAR AUTOMATIC AIR CONDITIONING SYSTEM : Door Control"
-HAC-27, "REAR AUTOMATIC AIR CONDITIONING SYSTEM : Temperature Control"
- Correction for input value of each sensor
Ambient sensor (setting temperature correction)
JMIIA0818GB
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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
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SYSTEMHAC-25
< SYSTEM DESCRIPTION > [AUTOMATIC AIR CONDITIONING]
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When rear blower motor is activated, A/C auto amp. gradually increases duty ratio of rear blower motor control signal to prevent a
sudden increase in discharge air flow.
It takes approximately 8 seconds for air flow to reach HI from LOW.
LOW COOLANT TEMPERATURE STARTING CONTROL
If the engine coolant temperature is 56 °C (133 °F) or less, to prevent
a cold discharged air flow, A/C auto amp. suspends rear blower
motor activation for the maximum 150 seconds depending on target
rear air mix door opening angle. After this, rear blower motor control
signal is increased gradually, and rear blower motor is activated.
HIGH IN-VEHICLE TEMPERATURE STARTING CONTROL
When front evaporator fin temperature is high [intake sensor value is 35°C (95 °F) or more], to prevent a hot
discharged air flow, A/C auto amp. suspends rear blower motor activation for approximately 3 seconds so that
rear evaporator is cooled by refrigerant.
FAN SPEED CONTROL AT DOOR MOTOR OPERATION
When rear mode door motor is activated while air flow is more than the specified value, A/C auto amp.
reduces temporarily fan speed wo t hat rear mode door moves smoothly.
REAR AUTOMATIC AIR CONDITIONING SYSTEM : Air Outlet ControlINFOID:0000000006275872
While air outlet is in automatic control, A/C auto amp. selects the
rear mode door position depending on a target rear air mix door
angle and outlet air temperature calculated from sunload.
JMIIA0739GB
JMIIA0740GB
JMIIA0733GB
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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
JMIIA0729GB
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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SYSTEMHAC-27
< SYSTEM DESCRIPTION > [AUTOMATIC AIR CONDITIONING]
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AIR DISTRIBUTION
REAR AUTOMATIC AIR CONDITIONING SYSTEM : Temperature ControlINFOID:0000000006275874
When ignition switch is in the ON position, A/C auto amp. always
automatically controls temperatur e regardless of rear air condition-
ing operational state.
A/C auto amp. calculates the target rear air mix door opening
angle depending on set temperature, in-vehicle temperature (rear
side), ambient temperature, and sunload.
Rear air mix door is controlled depending on the comparison of
current rear air mix door opening angle and target front air mix
door opening angle.
Regardless of in-vehicle temperature (rear side), ambient tempera-
ture, and sunload, rear air mix door is fixed at the fully cold position
when set temperature is 18.0 °C (60 °F), and at the fully hot position
when set temperature is 32.0 °C (90 °F).
ACCS (ADVANCED CLIMATE CONTROL SYSTEM)
MODE switch VENT C —
B/L D —
FOOT E —
Temperature control dial (front A/C control)
Temperature control switch (rear A/C control) 18.0
°C (60 °F) — A
18.5 °C (61 °F) ⇔
31.5 °C (89 °F) —AUTO
32.0 °C (90 °F) — B
OFF switch AUTO —
Switch/Dial position
Door position
Rear mode door Rear air mix door
Discharge air flow
Mode position Air outlet/distribution
VENT FOOT
100% —
62% 38%
—100%
JMIIA0734GB
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HAC-40
< SYSTEM DESCRIPTION >[AUTOMATIC AIR CONDITIONING]
DIAGNOSIS SYSTEM (HVAC)
ACTIVE TEST
Check each output device
COMP REQ SIG [On/Off] Displays A/C switch ON/OFF status transmitted to other units via CAN communication
FAN REQ SIG [On/Off]Displays front blower motor ON/OFF status transmitted to other units via CAN commu-
nication
FAN DUTY Duty ratio of front blower motor judged by A/C auto amp.
XM Target discharge front air temperature (driver side) judged by A/C auto amp. depending
on the temperature setting and the value from each sensor
PASS SUNL CAL [w/m
2]Sunload value (passenger side) calculated by A/C auto amp.
PASS SUNLOAD SEN [w/m
2]Sunload sensor value converted from sunload sensor signal (passenger side) received
from sunload sensor
PA TARGET A/TEMP Target discharge front air temperature (passenger side) judged by A/C auto amp. de-
pending on the temperature setting and the value from each sensor
RRIN TEMP SEN [ °C ( °F)] Rear in-vehicle sensor value converted from rear in-vehicle sensor signal received from
rear in-vehicle sensor.
RRIN TEMP CAL [ °C ( °F)] In-vehicle temperature (rear side) value calculated by A/C auto amp.
RR INT TMP CL [ °C ( °F)] Rear evaporator fin temperature value calculated by A/C auto amp.
RRFAN REQ SIG [On/Off] Displays rear blower motor ON/OFF status transmitted to other units via CAN communi-
cation
RR FAN DUTY Duty ratio of rear blower motor judged by A/C auto amp.
RR XM Target discharge rear air temperature (driver side) judged by A/C auto amp. depending
on the temperature setting and the value from each sensor
ENG COOL TEMP [ °C ( °F)] Engine coolant temperature signal value received from ECM via CAN communication
VEHICLE SPEED [km/h
(mph)] Vehicle speed signal value received from combination meter via CAN communication
Monitor item [Unit] Description
Te s t i t e m D e s c r i p t i o n
HVAC TEST The operation check of air conditioning system can be performed by selecting the mode.
Refer to the following table for the conditions of each mode.
Te s t i t e m
MODE 1 MODE 2 MODE 3 MODE 4 MODE 5 MODE 6 MODE 7
Front mode door motor posi-
tion VENT VENT B/L B/L FOOT D/F DEF
Intake door motor position REC REC 20% FRE 20% FRE FRE FRE FRE
Front air mix door motor (driver
side) position FULL COLD FULL COLD FULL COLD FULL HOT FULL HOT FULL HOT FULL HOT
Front air mix door motor (pas-
senger side) position FULL COLD FULL COLD FULL COLD FULL HOT FULL HOT FULL HOT FULL HOT
Front blower motor control sig-
nal duty ratio 35% 35% 59% 59% 89% 89% 35%
Magnet clutch ON ON ON ON OFF OFF ON
Upper ventilator door motor
position OPEN CLOSE OPEN CLOSE CLOSE CLOSE CLOSE
Rear mode door motor posi-
tion VENT VENT B/L B/L FOOT FOOT FOOT
Rear air mix door motor posi-
tion FULL COLD FULL COLD FULL COLD FULL HOT FULL HOT FULL HOT FULL HOT
Rear blower motor control sig-
nal duty ratio 35% 35% 59% 59% 89% 89% 35%
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HAC-44
< ECU DIAGNOSIS INFORMATION >[AUTOMATIC AIR CONDITIONING]
A/C AUTO AMP.
11
(W) GroundCommunication signal
(A/C auto amp.
→Rear A/C
control) Output Ignition switch ON
14
(O/L) GroundFront blower motor control
signal
Output Ignition switch ON
Front fan speed: 1st
speed (manual)
16
(R/G) Ground Each door motor LIN signal Input/
Output Ignition switch ON
17
(L/Y) GroundEach door motor power sup-
ply
Output Ignition switch ON 12 V
21
(P) —CAN-L
Input/
Output ——
22
(B) —Ground — — —
23
(GR/L) Ground Ignition power supply Input Ignition switch ON Battery voltage
25
*1, *
(R) ———— —
26
(B) — Sensor ground — — —
27
(GR) GroundFront in-vehicle sensor sig-
nal
Input Ignition switch ON 0 – 4.8 V
Output voltage varies with in-vehi- cle temperature (front side)
28
(R) Ground Intake sensor signal Input Ignition switch ON 0 – 4.8 V
Output voltage varies with front evaporator fin temperature
29
(O) Ground
Sunload sensor (passenger
side) signal Input Ignition switch ON 0 – 4.8 V
Output voltage varies with sunload
(passenger side) amount
31
(O/L) GroundCommunication signal
(Rear A/C control
→A/C auto
amp.) Input Ignition switch ON
Te r m i n a l N o .
(Wire color) Description
ConditionVa l u e
(Approx.)
+ − Signal name Input/
Output
SJIA1521J
JSIIA0096ZZ
SJIA1453J
SJIA1522J
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HAC-46
< ECU DIAGNOSIS INFORMATION >[AUTOMATIC AIR CONDITIONING]
A/C AUTO AMP.
*1: With ACCS (advanced climate control system)
*2: Perform self-diagnosis under sunshine. When performi
ng indoors, aim a light (more than 60 W) at sunload
sensor, otherwise self-diagnosis indicates even though the sunload sensor is functioning normally.
NOTE:
If all of door motor DTCs (B2632, B2633, B2634, B2635, B2636, B2637, B2638, B2639, B263D, B263E,
B263F, B2654, B2655, B2661, B2662, B2663, B2664, B 2665, B2666, B2669, and B266A) are detected, check
door motor communication circuit. Refer to HAC-120, "
Diagnosis Procedure".
B262A*1GAS SENSOR HAC-83, "DTC Logic"
B262B*1GAS SENSORHAC-83, "DTC Logic"
B2630*2SUNLOAD SENSORHAC-86, "DTC Logic"
B2631*2SUNLOAD SENSORHAC-86, "DTC Logic"
B2632 DR AIRMIX DOOR MOT HAC-89, "DTC Logic"
B2633 DR AIRMIX DOOR MOTHAC-89, "DTC Logic"
B2634 PASS AIR MIX DOOR MOTHAC-91, "DTC Logic"
B2635 PASS AIR MIX DOOR MOTHAC-91, "DTC Logic"
B2636 DR VENT DOOR FAILHAC-93, "DTC Logic"
B2637 DR B/L DOOR FAILHAC-93, "DTC Logic"
B2638 DR D/F1 DOOR FAILHAC-93, "DTC Logic"
B2639 DR DEF DOOR FAILHAC-93, "DTC Logic"
B263D FRE DOOR FAIL HAC-95, "DTC Logic"
B263E 20P FRE DOOR FAILHAC-95, "DTC Logic"
B263F REC DOOR FAILHAC-95, "DTC Logic"
B2654 D/F2 DOOR FAILHAC-93, "DTC Logic"
B2655 B/L2 DOOR FAILHAC-93, "DTC Logic"
B2657*1GAS SENSOR CIRCUITHAC-83, "DTC Logic"
B2658*1GAS SENSOR CIRCUITHAC-83, "DTC Logic"
B2661 UPPER VENT DOOR MOT HAC-97, "DTC Logic"
B2662 UPPER VENT DOOR MOTHAC-97, "DTC Logic"
B2663 UPPER VENT DOOR MOTHAC-97, "DTC Logic"
B2664 REAR AIR MIX DOOR MOTHAC-99, "DTC Logic"
B2665 REAR AIR MIX DOOR MOTHAC-99, "DTC Logic"
B2666 REAR MODE DOOR MOTHAC-101, "DTC Logic"
B2667*2PASS SUNLOAD SENSORHAC-103, "DTC Logic"
B2668*2PASS SUNLOAD SENSORHAC-103, "DTC Logic"
B2669 REAR MODE DOOR MOT HAC-101, "DTC Logic"
B266A REAR MODE DOOR MOT HAC-101, "DTC Logic"
B266B REAR IN-VEHICLE SENHAC-106, "DTC Logic"
B266C REAR IN-VEHICLE SEN HAC-106, "DTC Logic"
B27B0 A/C AUTO AMP.HAC-109, "DTC Logic"
DTCItems
(CONSULT-III screen terms) Reference
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HAC-68
< BASIC INSPECTION >[AUTOMATIC AIR CONDITIONING]
SYSTEM SETTING
SYSTEM SETTING
FRONT AUTOMATIC AIR CONDITIONING SYSTEM
FRONT AUTOMATIC AIR CONDITIONING SYST
EM : Temperature Setting Trimmer
(Front)
INFOID:0000000006275896
DESCRIPTION
If the temperature felt by the customer is different from the front air flow temperature controlled by the temper-
ature setting, the A/C auto amp. control temperature can be adjusted to compensate for the temperature set-
ting.
HOW TO SET
With CONSULT-III
Perform “TEMP SET CORRECT” of HVAC work support item.
NOTE:
When −3.0 °C ( −6 °F) is corrected on the temperature setting set as 25.0 °C (77 °F) the temperature controlled
by A/C auto amp. is 25.0 °C (77 °F) −3.0 °C ( −6 °F) = 22.0 °C (72 °F) and the temperature becomes lower than
the temperature setting.
When the battery cable is disconnected from the negativ e terminal or when the battery voltage becomes 10
V or less, the setting of the difference between t he set temperature and control temperature may be can-
celled.
FRONT AUTOMATIC AIR CONDITIONING SYSTEM : Foot Position Setting Trimmer
INFOID:0000000006275897
DESCRIPTION
In FOOT mode, the air blowing to DEF can change ON/OFF.
HOW TO SET
With CONSULT-III
Perform the “BLOW SET” of HVAC work support item.
Work support items Display ( °C) Display ( °F)
TEMP SET CORRECT 3.0 6
2.5 5
2.0 4
1.5 3
1.0 2
0.5 1
0 (initial status) 0 (initial status) −0.5 −1
− 1.0 −2
− 1.5 −3
− 2.0 −4
− 2.5 −5
− 3.0 −6
Work support items Display Defroster door position
Auto control Manual control
BLOW SET Mode1 OPEN CLOSE
Mode2 (initial status) OPEN OPEN
Mode3 CLOSE OPEN
Mode4 CLOSE CLOSE
Revision: 2010 May2011 QX56