2007 INFINITI QX56 cooling

ATC-4
< SERVICE INFORMATION >
PRECAUTIONS
not have dedicated recovery equipment, you may contact a local refrigerant product retailer for available ser-
vice. This refrigerant must be disposed of in acco rdance with all federal and local regulations. In addition,
replacement of all refrigerant system components on the vehicle is recommended.
• If the vehicle is within the warranty period, the air conditioner warranty is void. Please contact NISSAN Cus-
tomer Affairs for further assistance.
General Refrigerant PrecautionINFOID:0000000003533220
WARNING:
• Do not release refrigerant into th e air. Use approved recovery/recycling equipment to capture the
refrigerant every time an air conditioning system is discharged.
• Always wear eye and hand protection (goggles and gloves) when working with any refrigerant or air
conditioning system.
• Do not store or heat refrigerant containers above 52 °C (125 °F).
• Do not heat a refrigerant container with an open flame; if container warming is required, place the
bottom of the container in a warm pail of water.
• Do not intentionally drop, puncture, or incinerate refrigerant containers.
• Keep refrigerant away from open flames: poisonou s gas will be produced if refrigerant burns.
• Refrigerant will displace oxygen, therefore be certa in to work in well ventilated areas to prevent suf-
focation.
• Do not pressure test or leak test HFC-134a (R-134a) service equipment and/or vehicle air condition-
ing systems with compressed air during repair. Some mixtures of air and HFC-134a (R-134a) have
been shown to be combustible at elevated pressures. These mixtures, if ignited, may cause injury or
property damage. Additional heal th and safety information may be obtained from refrigerant manu-
facturers.
Precaution for Leak Detection DyeINFOID:0000000003533221
• The A/C system contains a fluorescent leak detection dye used for locating refrigerant leaks. An ultraviolet
(UV) lamp is required to illuminate the dye when inspecting for leaks.
• Always wear fluorescence enhancing UV safety goggles to protect your eyes and enhance the visibility of
the fluorescent dye.
• The fluorescent dye leak detector is not a replacement for an electronic refrigerant leak detector. The fluo-
rescent dye leak detector should be used in conjuncti on with an electronic refrigerant leak detector (J-
41995).
• For your safety and the customer's satisfaction, r ead and follow all manufacturer's operating instructions and
precautions prior to performing work.
• A compressor shaft seal should not be repaired because of dye seepage. The compressor shaft seal should only be repaired after confirming the leak with an electronic refrigerant leak detector (J-41995).
• Always remove any dye from the leak area after repairs are complete to avoid a misdiagnosis during a future
service.
• Do not allow dye to come into contact with painted body panels or interior components. If dye is spilled,
clean immediately with the approved dye cleaner. Fluoresc ent dye left on a surface for an extended period of
time cannot be removed .
• Do not spray the fluorescent dye cleaning agent on hot surfaces (engine exhaust manifold, etc.).
• Do not use more than one refrigerant dye bottle (1/4 ounce / 7.4 cc) per A/C system.
• Leak detection dyes for HFC-134a (R-134a) and CFC-12 (R -12) A/C systems are different. Do not use HFC-
134a (R-134a) leak detection dye in CFC-12 (R-12) A/ C systems or CFC-12 (R-12) leak detection dye in
HFC-134a (R-134a) A/C systems or A/C system damage may result.
• The fluorescent properties of the dye will remain for ov er three (3) years unless a compressor failure occurs.
A/C Identification LabelINFOID:0000000003533222
Vehicles with factory installed fluorescent dye have this identification label on the underside of hood.
Precaution for Refrigerant ConnectionINFOID:0000000003533223
A new type refrigerant connection has been introduced to al l refrigerant lines except the following locations.
• Expansion valve to cooling unit
• Evaporator pipes to evaporator (inside cooling unit)
• Refrigerant pressure sensor
FEATURES OF NEW TYPE REFRIGERANT CONNECTION

PRECAUTIONSATC-7
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Rear A/C
CAUTION:
The new and former refrigerant connections use diffe rent O-ring configurations. Do not confuse O-
rings since they are not interchangeable. If a wrong O-ring is installed, refrigerant will leak at or
around the connection.
O-Ring Part Numbers and Specifications
WJIA2315E
1. Rear heater and cooling unit assembly 2. Rear A/C pipes 3. Rear A/C heater core pipes
4. Rear heater core hose 5. Rear blower motor 6. Underfloor rear A/C pipes
7. Underfloor rear heater core pipes A. Bolt torque specifications B. Leak checking order (l - r)
C. Tightening torque D. Wrench size E. O-ring size
⇐ Front
NOTE: The O-ring size 8 is the high-side and the O-ring size 16 is the low-side.

ATC-18
< SERVICE INFORMATION >
REFRIGERATION SYSTEM
REAR REFRIGERATION SYSTEM
1. Defroster nozzle 2. LH side demister duct 3. LH ventilator duct
4. RH side demister duct 5. RH ventilator duct 6. Center ventilator duct
7. Front heater and cooling unit assembly 8. Floor duct 9. Clips
10. Heat duct
WJIA0956E

REFRIGERATION SYSTEMATC-19
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4. Rear upper overhead duct
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ATC-20
< SERVICE INFORMATION >
OIL
OIL
Maintenance of Oil Quantity in CompressorINFOID:0000000003533232
The oil in the compressor circulates through the system with the refrigerant. Add oil to compressor when
replacing any component or after a large refrigerant leakage has occurred. It is important to maintain the spec-
ified amount.
If oil quantity is not maintained properly, the following malfunctions may result:
• Lack of oil: May lead to a seized compressor
• Excessive oil: Inadequate cooling (thermal exchange interference)
OIL
Name: NISSAN A/C System Oil Type S or equivalent
CHECKING AND ADJUSTING
CAUTION:
If excessive oil leakage is noted, do no t perform the oil return operation.
Start the engine and set the following conditions:
Test Condition
• Engine speed: Idling to 1,200 rpm
• A/C switch: On
• Blower fan speed: MAX position
• Temp. control: Optional [Set so that intake air temperature is 25 ° to 30 ° C (77 ° to 86 °F)]
• Intake position: Recirculation ( )
• Perform oil return operation for about ten minutes
Adjust the oil quantity according to the following table.
Oil Adjusting Procedure for Components Replacement Except Compressor
After replacing any of the following major component s, add the correct amount of oil to the system.
Amount of oil to be added :
• *1: If refrigerant leak is small, no addition of oil is needed.
Oil Adjustment Procedure for Compressor Replacement
Part replaced Oil to be added to system
Remarks
Amount of oil
m (US fl oz, Imp fl oz)
Front evaporator 75 (2.5, 2.6) —
Rear evaporator 75 (2.5, 2.6) —
Condenser 75 (2.5, 2.6) —
Liquid tank 5 (0.2, 0.2) Add if compressor is not replaced.
In case of refrigerant leak 30 (1.0, 1.1) Large leak
— Small leak *1

ATC-32
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
How to Perform Trouble Diagnosis for Quick and Accurate Repair
INFOID:0000000003533243
WORK FLOW
SYMPTOM TABLE
Component Parts and Harness Connector LocationINFOID:0000000003533244
ENGINE COMPARTMENT
*1AT C - 5 0 , "Operational Check (Front)"
or AT C - 5 1 , "
Operational Check
(Rear)" .
SHA900E
Symptom Reference Page
A/C system does not come on. Go to Trouble Diagnosis Procedure for A/C System. AT C - 5 2
A/C system display is malfunctioning. Go to Navigation System. AV- 7 3
A/C system cannot be controlled. Go to Self-diagnosis Function.AT C - 4 8 , "
A/C Sys-
tem Self-Diagno-
sis Function"
Air outlet does not change.
Go to Trouble Diagnosis Procedure for Mode Door Motor. AT C - 5 4
Mode door motor is malfunctioning.
Discharge air temperature does not change.
Go to Trouble Diagnosis Procedure for Air Mix Door Motor. AT C - 5 9
Air mix door motor is malfunctioning.
Intake door does not change.
Go to Trouble Diagnosis Procedure for Intake Door Motor. AT C - 7 0
Intake door motor is malfunctioning.
Defroster door motor is malfunctioning. Go to Trouble Diagnosis Procedure for Defroster Door Motor. AT C - 7 4
Front blower motor operation is malfunction-
ing.Go to Trouble Diagnosis Procedure for Front Blower Motor.
AT C - 7 8
Rear blower motor operation is malfunction-
ing.Go to Trouble Diagnosis Procedure for Rear Blower Motor.
AT C - 8 5
Rear discharge air temperature and/or air
outlet does not change.Go to Trouble Diagnosis Procedure for Rear Air Control circuit.
AT C - 9 3
Magnet clutch does not engage. Go to Trouble Diagnosis Procedure for Magnet Clutch. AT C - 9 6
Insufficient cooling Go to Trouble Diagnosis Procedure for Insufficient Cooling.AT C - 1 0 0
Insufficient heating Go to Trouble Diagnosis Procedure for Insufficient Heating.AT C - 1 0 8
Noise Go to Trouble Diagnosis Procedure for Noise.AT C - 1 0 9
Self-diagnosis cannot be performed. Go to Trouble Diagnosis Procedure for Self-diagnosis. AT C - 111
Memory function does not operate. Go to Trouble Diagnosis Procedure for Memory Function.AT C - 11 2

TROUBLE DIAGNOSISATC-51
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1. Rotate temperature control dial (driver si de or passenger side) counterclockwise until 16 °C (60 °F) is dis-
played.
2. Check for cold air at appropriate discharge air outlets.
If NG, listen for sound of air mix door motor operat ion. If OK, go to trouble diagnosis procedure for ATC-100,
"Insufficient Cooling" . If air mix door motor appears to be malfunctioning, go to ATC-59, "Air Mix Door Motor
Circuit" or ATC-59, "Air Mix Door Motor Circuit".
If OK, continue the check.
CHECKING TEMPERATURE INCREASE
1. Rotate temperature control dial clockw ise (driver side or passenger side) until 32°C (90 °F) is displayed.
2. Check for hot air at appropriate discharge air outlets.
If NG, listen for sound of air mix door motor operat ion. If OK, go to trouble diagnosis procedure for ATC-108,
"Insufficient Heating" . If air mix door motor appears to be malfunctioning, go to ATC-59, "Air Mix Door Motor
Circuit" or ATC-59, "Air Mix Door Motor Circuit".
If OK, continue with next check.
CHECK A/C SWITCH
1. Press A/C switch when AUTO switch is ON, or in manual mode.
2. A/C switch indicator will turn ON.
• Confirm that the compressor clutch engages (sound or visual inspection).
NOTE:
If current mode setting is DEF or D/F, compressor clutch may already be engaged.
If NG, go to trouble diagnosis procedure for ATC-96, "
Magnet Clutch Circuit" .
If OK, continue with next check.
CHECKING AUTO MODE
1. Press AUTO switch.
2. Display should indicate AUTO.
• If ambient temperature is warm, and selected temperat ure is cool, confirm that the compressor clutch
engages (sound or visual inspection). (Discharge air and blower speed will depend on ambient, in-vehi-
cle, and set temperatures.)
If NG, go to trouble diagnosis procedure for ATC-52, "
Power Supply and Ground Circuit for Front Air Control" ,
then if necessary, trouble diagnosis procedure for ATC-96, "
Magnet Clutch Circuit" .
If all operational checks are OK (symptom cannot be duplicated), go to malfunction Simulation Tests in AT C -
32, "How to Perform Trouble Diagnosis for Quick and Accurate Repair" and perform tests as outlined to simu-
late driving conditions environment . If symptom appears. Refer to ATC-32, "
How to Perform Trouble Diagnosis
for Quick and Accurate Repair", ATC-32, "How to Perform Trouble Diagnosis for Quick and Accurate Repair"
and perform applicable trouble diagnosis procedures.
Operational Check (Rear)INFOID:0000000003533250
The purpose of the operational check is to confirm that the system operates properly.
CHECKING BLOWER
1. Turn the rear blower control dial to swit ch position "1". Blower should operate on low speed.
2. Turn the rear blower control dial counterclockwis e to switch position "2", "3", and "4" until all speeds are
checked.
3. Leave blower on MAX speed.
If NG, go to trouble diagnosis procedure for ATC-85, "
Rear Blower Motor Circuit" .
If OK, continue the check.
CHECKING TEMPERATURE DECREASE
1. Rotate temperature and mode dial fully counterclockwise.
2. Check for cold air at appropriate discharge air outlets. Conditions : Engine running and at normal operating temperature

ATC-52
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
If NG, listen for sound of air mix door motor operation if OK, go to trouble diagnosis procedure for ATC-100,
"Insufficient Cooling" . If air mix door motor appears to be malfunctioning, go to ATC-59, "Air Mix Door Motor
Circuit".
If OK, continue the check.
CHECKING TEMPERATURE INCREASE
1. Rotate temperature and mode dial clockwise.
2. Check for hot air at appropriate discharge air outlets.
If NG, listen for sound of air mix door motor operat ion. If OK, go to trouble diagnosis procedure for ATC-108,
"Insufficient Heating". If air mix door motor appears to be malfunctioning, go to ATC-59, "Air Mix Door Motor
Circuit" .
If OK, continue the check.
Power Supply and Ground Circu it for Front Air ControlINFOID:0000000003533251
SYMPTOM: A/C system does not come on.
INSPECTION FLOW
1.CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - AUTO MODE
1. Press AUTO switch.
2. Display should indicate AUTO. Confirm that the compressor clutch engages (sound or visual inspection).
(Discharge air and blower speed will depend on am bient, in-vehicle and set temperatures.)
Can a symptom be duplicated?
YES >> GO TO 3.
NO >> GO TO 2.
2.PERFORM COMPLETE OPERATIONAL CHECK
Perform a complete operational check and check for any symptoms. Refer to ATC-50, "
Operational Check
(Front)".
Can a symptom be duplicated
YES >> Refer to ATC-32, "How to Perform Trouble Diagnosis for Quick and Accurate Repair".
NO >> System OK.
3.CHECK FOR SERVICE BULLETINS
Check for any service bulletins.
>> GO TO 4.
4.CHECK POWER AND GROUND CIRCUIT
Check main power supply and ground circuit. Refe r to "DIAGNOSTIC PROCEDURE FOR A/C SYSTEM".
OK or NG
OK >> System OK.
NO >> Replace front air control. Refer to ATC-123, "
Removal and Installation".
COMPONENT DESCRIPTION
Front Air Control
The front air control has a built-in microcomputer which processes
information sent from various sensors needed for air conditioner
operation. The air mix door motors, mode door motor, intake door
motor, defroster door motor, blower motor and compressor are then
controlled.
The front air control is unitized with control mechanisms. When the
various switches and temperature dials are operated, data is input to
the front air control.
Self-diagnostic functions are also built into the front air control to pro-
vide quick check of malfunctions in the auto air conditioner system.
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