2007 INFINITI QX56 check engine

TRANSMISSION ASSEMBLY
AT-225
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• When installing transmission to the engine, attach the bolts as shown.
NOTE:
*: No.2 bolt also secures air breather vent.
CAUTION:
• When replacing an engine or transmission you must make
sure the dowels are installed correctly during re-assembly.
• Improper alignment caused by missing dowels may cause
vibration, oil leaks or breakage of drivetrain components.
• Align the positions of bolts for drive plate with those of the torque
converter, and temporarily tighten the bolts. Then tighten the bolts
with the specified torque.
CAUTION:
• When turning crankshaft, turn it clockwise as viewed from the
front of the engine.
• After converter is installed to drive plate, rotate crankshaft
several turns and check to be sure that transmission rotates
freely without binding.
• Install crankshaft position sensor (POS).
• After completing installation check fluid leakage, fluid level and the
positions of A/T. Refer to AT-13, "
Checking Automatic Transmis-
sion Fluid (ATF)", AT-208, "Checking of A/T Position" and AT-208, "Adjustment of A/T Position".
Removal and Installation (4WD)INFOID:0000000003532482
COMPONENTS
Transmission to engine bolts : 113 N·m (12 kg-m,
83 ft-lb)
LCIA0371E
LCIA0335E
AWDIA0441GB

TRANSMISSION ASSEMBLY
AT-227
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17. Plug any openings such as the fluid charging pipe hole.
18. Remove A/T assembly to engine bolts using power tool.
19. Remove A/T assembly with transfer from vehicle.
CAUTION:
• Secure torque converter to prevent it from dropping.
• Secure A/T assembly to transmission jack.
20. Remove transfer from A/T assembly. Refer to TF-128, "
Removal and Installation".
INSPECTION
Installation and Inspection of Torque Converter
• After inserting a torque converter to a transmission, be sure to
check dimension A to ensure it is within specifications.
INSTALLATION
Installation of the remaining components is in the reverse order of removal, while paying attention to the fol-
lowing:
• When installing transmission to the engine, attach the bolts as shown.
NOTE:
*: No.2 bolt also secures air breather vent.
CAUTION:
• When replacing an engine or transmission you must make
sure the dowels are installed correctly during re-assembly.
• Improper alignment caused by missing dowels may cause
vibration, oil leaks or breakage of drivetrain components.
• Align the positions of bolts for drive plate with those of the torque
converter, and temporarily tighten the bolts. Then tighten the bolts
with the specified torque.
CAUTION:
• When turning crankshaft, turn it clockwise as viewed from the
front of the engine.
• After converter is installed to drive plate, rotate crankshaft
several turns and check to be sure that transmission rotates
freely without binding.
• Install crankshaft position sensor (POS).
• After completing installation, check fluid leakage, fluid level, and
the positions of A/T. Refer to AT-13, "
Checking Automatic Trans-
mission Fluid (ATF)", AT-208, "Checking of A/T Position" and AT-208, "Adjustment of A/T Position". Dimension A : 24.0 mm (0.94 in) or more
SAT017B
Transmission to engine bolts : 113 N·m (12 kg-m,
83 ft-lb)
LCIA0371E
LCIA0335E

PRECAUTIONSATC-9
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Precaution for Service of CompressorINFOID:0000000003533224
• Plug all openings to prevent moisture and foreign matter from entering.
• When the compressor is removed, store it in the same position as it is when mounted on the car.
• When replacing or repairing co mpressor, follow “Maintenance of Oil Quantity in Compressor”
exactly. Refer to ATC-20, "
Maintenance of Oil Quantity in Compressor".
• Keep friction surfaces between clutch and pulley clean . If the surface is contaminated with oil, wipe
it off by using a clean wast e cloth moistened with thinner.
• After compressor service operation, turn the compressor shaft by hand more than 5 turns in both
directions. This will equa lly distribute oil inside the compresso r. After the compressor is installed,
let the engine idle and oper ate the compressor for 1 hour.
• After replacing the compressor magnet clutch, ap ply voltage to the new one and check for normal
operation. Refer to ATC-155, "
Removal and Installation for Compressor Clutch".
Precaution for Service EquipmentINFOID:0000000003533225
RECOVERY/RECYCLING EQUIPMENT
Follow the manufacturer's instructions for machine operation and machine maintenance. Never introduce any
refrigerant other than that specified into the machine.
ELECTRONIC LEAK DETECTOR
Follow the manufacturer's instructions fo r tester operation and tester maintenance.
VACUUM PUMP
1. Plug 2. O-ring A. Torque wrench
B. Apply oil C. Do not apply oil to threads D. NG (no good)
E. OK (okay) F. Inflated portion
WJIA1774E

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
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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

ATC-50
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TROUBLE DIAGNOSIS
Operational Check (Front)
INFOID:0000000003533249
The purpose of the operational check is to confirm that the system operates properly.
CHECKING MEMORY FUNCTION
1. Set the temperature to 90 °F or 32 °C.
2. Turn front blower control dial counterclockwise until system shuts OFF.
3. Turn ignition switch OFF.
4. Turn ignition switch ON.
5. Press the AUTO switch.
6. Confirm that the set temperature remains at previous temperature.
7. Turn front blower control counterclockwise until system shuts OFF.
If NG, go to trouble diagnosis procedure for ATC-112, "
Memory Function".
If OK, continue with next check.
CHECKING BLOWER
1. Turn front blower control clockwise, blower s hould operate on low speed. The blower symbol should have
one blade lit (on display).
2. Turn the front blower control dial again, and c ontinue checking blower speed and blower symbol until all
speeds are checked.
3. Leave blower on MAX speed.
If NG, go to trouble diagnosis procedure for ATC-78, "
Front Blower Motor Circuit".
If OK, continue with next check.
CHECKING DISCHARGE AIR
1. Press MODE switch four times and the DEF ( ) switch.
2. Each position indicator should change shape (on display).
3. Confirm that discharge air comes out according to the air distribution table. Refer to ATC-26, "
Discharge
Air Flow".
Mode door position is checked in the next step.
If NG, go to trouble diagnosis procedure for ATC-54, "
Mode Door Motor Circuit" .
If OK, continue the check.
NOTE:
Confirm that the compressor clutch is engaged (sound or vis ual inspection) and intake door position is at fresh
when the DEF or D/F is selected.
CHECKING RECIRCULATION ( , ONLY)
1. Press recirculation ( ) switch one time. Recirculation indicator should illuminate.
2. Press recirculation ( ) switch one more time. Recirculation indicator should go off.
3. Listen for intake door position change (blower sound should change slightly).
If NG, go to trouble diagnosis procedure for ATC-70, "
Intake Door Motor Circuit" .
If OK, continue the check.
NOTE:
Confirm that the compressor clutch is engaged (sound or vis ual inspection) and intake door position is at fresh
when the DEF or D/F is selected. REC ( ) is not allowed in DEF ( ) D/F ( ) or FOOT ( ).
CHECKING TEMPERATURE DECREASE
90 Stuck button ATC-123, "Removal and Installation"
92 Mode door motor circuit failureAT C - 5 4 , "Mode Door Motor Circuit"
Code No. Reference page
Conditions : Engine running and at normal operating temperature

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

TROUBLE DIAGNOSISATC-79
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1.CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - FRONT BLOWER
1. Rotate the front blower control dial clockwise. Blower should operate.
2. Rotate the front blower control dial clockwise, and continue checking blower speed and fan symbol until
all speeds are checked.
Can the symptom be duplicated?
YES >> GO TO 3.
NO >> GO TO 2.
2.CHECK FOR ANY SYMPTOMS
Perform a complete operational check for any symptoms. Refer to ATC-50, "
Operational Check (Front)" .
Does another symptom exist?
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.PERFORM SELF-DIAGNOSIS
Perform self-diagnosis to check for any codes. Refer to ATC-48, "
A/C System Self-Diagnosis Function" .
Are any self-diagnosis codes present?
YES >> Refer to ATC-48, "A/C System Self-Diagnosis Function" .
NO >> GO TO 5.
5.CHECK BLOWER MOTOR OPERATION
Check and verify blower motor operates manually in all speeds.
Does blower motor operate in all speeds?
YES >> GO TO 6.
NO >> Refer to "DIAGNOSTIC PROCEDURE FOR BLOWER MOTOR".
6.CHECK ENGINE COOLANT TEMPERATURE SENSOR CIRCUIT
Check engine coolant temperature sensor circuit. Refer to EC-205
.
OK or NG?
OK >> GO TO 7.
NG >> Refer to EC-207, "
Diagnosis Procedure".
7.RECHECK FOR ANY SYMPTOMS
Perform a complete operational check for any symptoms. Refer to ATC-50, "
Operational Check (Front)" .
Does another symptom exist?
YES >> Refer to ATC-32, "How to Perform Trouble Diagnosis for Quick and Accurate Repair" .
NO >> Replace front air control. Refer to ATC-123, "
Removal and Installation".
SYSTEM DESCRIPTION
Component Parts
Blower speed control system components are:• Front air control
• Variable blower control
• Front blower motor relay
• Front blower motor
• In-vehicle sensor
• Ambient sensor
• Optical sensor
• Intake sensor