2009 INFINITI QX56 air condition

AUTOMATIC AIR CONDITIONER SYSTEMHAC-13
< FUNCTION DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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AUTOMATIC AIR CONDITIONER SYSTEM
Control System DiagramINFOID:0000000003775331
CONTROL SYSTEM
The control system consists of input sensors, switches, the A/C auto amp.(microcomputer) and outputs.
The relationship of these components is shown in the figure below:
Control System DescriptionINFOID:0000000003775332
CONTROL OPERATION
AWIIA0088GB
Revision: December 20092009 QX56

HAC-14
< FUNCTION DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
AUTOMATIC AIR CONDITIONER SYSTEM
A/C auto amp.
DISPLAY SCREEN
Displays the operational status of the system.
AUTO SWITCH
• The compressor, intake door, air mix doors, outlet
doors and blower speed are automatically controlled so
that the in-vehicle temperature will reach, and be mainta ined at the set temperature selected by the operator.
• When pressing AUTO switch, air inlet, air outlet, bl ower speed, and discharge air temperature are automati-
cally controlled.
TEMPERATURE CONTROL DIAL (DRIVER)
Increases or decreases the set temperature.
TEMPERATURE CONTROL DIAL (PASSENGER)
Increases or decreases the set temperature.
RECIRCULATION ( ) SWITCH
• When REC switch is ON, REC switch indicator turns ON, and air inlet is set to REC.
• When REC switch is turned OFF, or when compressor is turned from ON to OFF, REC switch is automati-
cally turned OFF. REC mode can be re-entered by pressing REC switch again.
• REC switch is not operated when DEF switch is tur ned ON, at the D/F position, or in floor position.
DEFROSTER ( ) SWITCH
Positions the air outlet doors to the defrost position. Al so positions the intake doors to the outside air position,
and turns A/C compressor ON.
REAR WINDOW DEFOGGER SWITCH
When switch is ON, rear window and door mirrors are defogged.
OFF SWITCH
The compressor and blower are OFF, the intake doors are set to the outside air position, and the air outlet
doors are set to the foot (75% foot and 25% defrost) position.
A/C SWITCH
The compressor is ON or OFF.
(Pressing the A/C switch when the AUTO switch is ON will turn off the A/C switch and compressor.)
MODE SWITCH
Controls the air discharge outlets.
FRONT BLOWER CONTROL SWITCHES
Manually control the blower speed.
AWIIA0081ZZ
Revision: December 20092009 QX56

AUTOMATIC AIR CONDITIONER SYSTEMHAC-15
< FUNCTION DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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Rear Air Controls
REAR TEMPERATURE CONTROL DIAL (FRONT/REAR)
The temperature increases or dec reases the set temperature.
REAR MODE SWITCHES (FRONT/REAR)
Controls the air discharge outlets.
REAR BLOWER CONTROL DIAL (FRONT)
When the REAR CTRL switch is in the off (indicator off) the rear air control (front) controls the rear blower
motor speed regardless of the rear air control (rear) blow er control dial (rear) position. The rear air control
(front) controls the blower motor speed.
REAR BLOWER CONTROL DIAL (REAR)
When the REAR CTRL switch is in the on (indicator on) the rear air control (rear) controls the rear blower
motor speed regardless of the rear air control (front) blow er control dial (front) position. The rear air control
(rear) controls the blower motor speed.
MAGNET CLUTCH CONTROL
When A/C switch or DEF switch is pressed, A/ C auto amp. inputs compressor ON signal to BCM.
BCM sends compressor ON signal to ECM and A/C auto amp., via CAN communication line.
ECM judges whether compressor can be turned ON, based on each sensor status (refrigerant pressure sen-
sor signal, throttle angle sensor, etc.). If it judges compressor can be turned ON, it sends compressor ON sig-
nal to IPDM E/R, via CAN communication line.
AWIIA0082ZZ
1. Rear air control (front )2. Rear air control (rear)
AWIIA1069GB
Revision: December 20092009 QX56

HAC-16
< FUNCTION DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
AUTOMATIC AIR CONDITIONER SYSTEM
Upon receipt of compressor ON signal from ECM, IPDM E/R turns air conditioner relay ON to operate com-
pressor.
Discharge Air Flow (Front)INFOID:0000000003775333
Discharge Air Flow (Rear)INFOID:0000000003775334

Mode door positionAir outlet/distribution
Vent Foot Defroster
95% 5% —
60% 40% —
—7 0% 3 0%
—6 0% 4 0%
—1 0% 9 0%
AWIIA0818ZZ
Revision: December 20092009 QX56

AUTOMATIC AIR CONDITIONER SYSTEMHAC-17
< FUNCTION DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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Mode door position Air outlet/distribution
Ve n t F o o t
100% —
50% 50%
—1 00 %
WJIA0541E
Revision: December 20092009 QX56

HAC-18
< FUNCTION DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
AUTOMATIC AIR CONDITIONER SYSTEM
Switches And Their Cont rol Function (Front)
INFOID:0000000003775335
WJIA1680E
AWIIA0083GB
Revision: December 20092009 QX56

AUTOMATIC AIR CONDITIONER SYSTEMHAC-19
< FUNCTION DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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Switches And Their C ontrol Function (Rear)INFOID:0000000003775336
AWIIA0275GB
AWIIA0084GB
Revision: December 20092009 QX56

HAC-20
< FUNCTION DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
DIAGNOSIS SYSTEM (HVAC)
DIAGNOSIS SYSTEM (HVAC)
CONSULT-III Function (HVAC)INFOID:0000000003775338
CONSULT-III can display each diagnostic item using the diagnostic test modes shown following.
SELF-DIAGNOSIS
Display Item List
DATA MONITOR
Display Item List
Diagnostic mode
Description
SELF-DIAG RESULTS Displays A/C au to amp. self-diagnosis results.
DATA MONITOR Displays A/C auto amp. input/output data in real time.
CAN DIAG SUPPORT MNTR The result of transmit/receive diagnosis of CAN communication can be read. ECU PART NUMBER A/C auto amp. part number can be read.
DTC Description
Reference page
B2573 Battery voltage out of range CHG-8, "
Inspection Procedure"
B2578 In-vehicle sensor circuit out of range (low)
HAC-82, "In-Vehicle Sensor Diagnosis Procedure"B2579 In-vehicle sensor circuit out of range (high)
B257B Ambient sensor circuit short HAC-79, "
Ambient Sensor Diagnosis Procedure"B257C Ambient sensor circuit open
B257F Optical sensor (Driver) circuit open or short HAC-85, "
Optical Sensor Diagnosis Procedure".
B2580 Optical sensor (Passenger) circuit open or short
B2581 Intake sensor circuit short HAC-87, "
Intake Sensor Diagnosis Procedure"B2582 Intake sensor circuit open
U1000 CAN bus fault LAN-14, "
Trouble Diagnosis Flow Chart"
Monitor itemValue Contents
BATT VIA CAN "V" Displays battery voltage signal.
IGN VIA CAN "ON/OFF" Displays ignition switch signal.
DVR SUNLD SEN "w/m2" Displays optical sensor (driver) signal.
PAS SUNLD SEN "w/m2" Displays optical sensor (passenger) signal.
AMB TEMP SEN "° C" Displays ambient sensor signal.
EVAP TEMP SEN "° C" Displays intake sensor signal.
INCAR TMP SEN "° C" Displays in-vehicle sensor signal.
RR TEMPSET FR "V" Displays air mix door (front) set point signal.
RR TEMPSET RR "V" Displays air mix door (rear) set point signal.
MODE FDBCK "V" Displays mode door motor feedback signal.
DVR MIX FDBCK "V" Displays air mix door motor (driver) feedback signal.
PAS MIX FDBCK "V" Displays air mix door motor (passenger) feedback signal.
RR FDBCK "V" Displays air mix door motor (rear) feedback signal.
DEF FDBCK "V" Displays defroster door motor feedback signal.
Revision: December 20092009 QX56