EC-476
< SYMPTOM DIAGNOSIS >[VK56DE]
ENGINE CONTROL SYSTEM SYMPTOMS
1 - 6: The numbers refer to the order of inspection.
(continued on next page)
SYSTEM — ENGINE MECHANICAL & OTHER
Mass air flow sensor circuit
1
12 2
222 2 EC-103,
EC-109
Engine coolant temperature sensor circuit
333
EC-120,
EC-128
Air fuel ratio (A/F ) sensor 1 circuit EC-136
,
EC-140
,
EC-143
,
EC-146
,
EC-377
Throttle position sensor circuit 22EC-124
,
EC-185
,
EC-302
,
EC-304
,
EC-369
Accelerator pedal position sensor circuit 3 2 1 EC-280
,
EC-362
,
EC-365
,
EC-373
Knock sensor circuit 2 3 EC-195
Crankshaft position sensor (POS) circuit 2 2EC-198
Camshaft position sensor (PHASE) circuit 3 2 EC-202
Vehicle speed signal circuit 2 3 3 3 EC-271
Power steering pressure sensor circuit 2 3 3 EC-277
ECM 22333333333 EC-280,
EC-282
Intake valve timing control solenoid valve cir-
cuit 32 13223 3
EC-100
Transmission range signal circuit 3 3 3 3 3 EC-288
Refrigerant pressure sensor circuit 2 3 3 4EC-416
Electrical load signal circuit 3EC-390
Air conditioner circuit 223333333 3 2HAC-25
ABS actuator and electric unit (control unit) 4 BRC-37
SYMPTOM
Refer-
ence page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Revision: December 20092009 QX56
ENGINE CONTROL SYSTEM SYMPTOMSEC-477
< SYMPTOM DIAGNOSIS > [VK56DE]
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Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Fuel Fuel tank 5
5 FL-11
Fuel piping 5 5 5 5 5 5
FL-6
Va p o r l o c k —
Valve deposit 5 555 55 5 —
Poor fuel (Heavy weight gasoline,
Low octane) —
Air Air duct
55555 5 EM-25
Air cleaner
EM-25
Air leakage from air duct
(Mass air flow sensor — electric
throttle control actuator)
5555 EM-25
Electric throttle control actuator
EM-26
Air leakage from intake manifold/
Collector/GasketEM-26
Cranking Battery
111111
11
PG-77
Generator circuit
CHG-6
Starter circuit 3STR-8
Signal plate 6EM-45
Transmission range signal 4TM-44
Engine Cylinder head
55555 55 5 EM-68
Cylinder head gasket 4 3
Cylinder block
66666 66 6 4
EM-83
Piston
Piston ring
Connecting rod
Bearing
Crankshaft
Va l v e
mecha-
nism Timing chain
55555 55 5 EM-45
Camshaft
EM-53
Intake valve timing controlEM-53
Intake valve
3EM-68
Exhaust valve
Revision: December 20092009 QX56
EC-478
< SYMPTOM DIAGNOSIS >[VK56DE]
ENGINE CONTROL SYSTEM SYMPTOMS
1 - 6: The numbers refer to the order of inspection.Exhaust Exhaust manifold/Tube/Muffler/
Gasket 55555 55 5 EM-30
,
EX-
5Three way catalyst
Lubrica-
tion Oil pan/Oil strainer/Oil pump/Oil
filter/Oil gallery/Oil cooler
55555 55 5 EM-33
,
LU-
14 , LU-11 ,
LU-12
Oil level (Low)/Filthy oil LU-8, "In-spection"
Cooling Radiator/Hose/Radiator filler cap
55555 55 45 CO-15
Thermostat 5
CO-22
Water pumpCO-20
Water galleryCO-6
Cooling fan 5CO-18,
CO-
19
Coolant level (Low)/Contaminat-
ed coolant 5
CO-10
IVIS (INFINITI Vehicle Immobilizer System —
NATS) 11
SEC-6
SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Revision: December 20092009 QX56
EM-68
< ON-VEHICLE REPAIR >
CYLINDER HEAD
CYLINDER HEAD
Exploded ViewINFOID:0000000005885894
Removal and InstallationINFOID:0000000005885895
REMOVAL
1. Remove the engine assembly from the vehicle. Refer to EM-78, "Removal and Installation".
2. Remove the following components and related parts: • Drive belt auto tensioner and idler pulley. Refer to EM-14, "
Drive Belt Auto Tensioner and Idler Pulley".
• Generator assembly and bracket. Refer to CHG-20, "
Removal and Installation".
• Thermostat housing and hose. Refer to CO-22, "
Removal and Installation".
• Oil pan and oil strainer. Refer to EM-33, "
Removal and Installation".
• Fuel tube and fuel injector assembly. Refer to EM-40, "
Removal and Installation".
• Intake manifold. Refer to EM-26, "
Removal and Installation".
• Rocker cover. Refer to EM-38, "
Removal and Installation".
3. Remove the crankshaft pulley, front cover, oil pump, and timing chain. Refer to EM-45, "
Removal and
Installation".
4. Remove the camshaft sprockets and camshafts. Refer to EM-53, "
Removal and Installation".
5. Remove the cylinder head bolts in reverse of order shown.
6. Remove the cylinder heads.
INSPECTION AFTER REMOVAL
Cylinder Head Bolts Diameter
1. Harness bracket 2. Engine coolant temperature sensor 3. Washer
4. Cylinder head gasket (LH) 5. Cylinder head (RH) 6. Cylinder head bolt
7. Cylinder head gasket (RH) 8. Cylinder head (LH)
KBIA2528E
PBIC0068E
Revision: December 20092009 QX56
IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM)
EXL-121
< ECU DIAGNOSIS >
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IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE
ROOM)
Reference ValueINFOID:0000000004215514
VALUES ON THE DIAGNOSIS TOOL
Monitor Item ConditionValue/Status
MOTOR FAN REQ Engine idle speed Changes depending on engine
coolant temperature, air conditioner
operation status, vehicle speed,
etc.0 - 100 %
A/C COMP REQ A/C switch OFF
OFF
A/C switch ON ON
TA I L & C L R R E Q Lighting switch OFF
OFF
Lighting switch 1ST, 2ND, HI or AUTO (Light is illuminated) ON
HL LO REQ Lighting switch OFF
OFF
Lighting switch 2ND HI or AUTO (Light is illuminated) ON
HL HI REQ Lighting switch OFF
OFF
Lighting switch HI ON
FR FOG REQ Lighting switch 2ND or AUTO (Light
is illuminated) Front fog lamp switch OFF OFF
• Front fog lamp switch ON
• Daytime light activated (Canada
only) ON
HL WASHER REQ NOTE:
This item is displayed, but cannot be monitored.
OFF
FR WIP REQ Ignition switch ON Front wiper switch OFF
STOP
Front wiper switch INT 1LOW
Front wiper switch LO LOW
Front wiper switch HI HI
WIP AUTO STOP Ignition switch ON Front wiper stop position
STOP P
Any position other than front wiper
stop position ACT P
WIP PROT Ignition switch ON Front wiper operates normally OFF
Front wiper stops at fail-safe opera-
tion
BLOCK
ST RLY REQ Ignition switch OFF or ACC
OFF
Ignition switch START ON
IGN RLY Ignition switch OFF or ACC
OFF
Ignition switch ON ON
RR DEF REQ Rear defogger switch OFF
OFF
Rear defogger switch ON ON
OIL P SW Ignition switch OFF, ACC or engine running
OPEN
Ignition switch ON CLOSE
DTRL REQ Daytime light system requested OFF with CONSULT-III.
OFF
Daytime light system reques ted ON with CONSULT-III. ON
HOOD SW Hood closed.
OFF
Hood open. ON
Revision: December 20092009 QX56
SERVICE INFORMATION FOR ELECTRICAL INCIDENTGI-35
< BASIC INSPECTION >
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• Do not apply excessive shock to the control unit by dropping or hit- ting it.
• Be careful to prevent condensation in the control unit due to rapid
temperature changes and do not let water or rain get on it. If water
is found in the control unit, dry it fully and then install it in the vehi-
cle.
• Be careful not to let oil to get on the control unit connector.
• Avoid cleaning the control unit with volatile oil.
• Do not disassemble the control unit, and do not remove the upper and lower covers.
• When using a DMM, be careful not to let test probes get close to each other to prevent the power transistor in the control unit from
damaging battery voltage because of short circuiting.
• When checking input and output signals of the control unit, use the specified check adapter.
How to Check TerminalINFOID:0000000003771214
CONNECTOR AND TERMINAL PIN KIT
• Use the connector and terminal pin kits listed below when replacing connectors or terminals.
• The connector and terminal pin kits contain some of the most commonly used NISSAN/INFINITI connectors
and terminals. For detailed connector and terminal pin r eplacement procedures, refer to the latest NISSAN/
INFINITI CONNECTOR AND TERMINAL PIN SERVICE MANUAL.
SAIA0255E
SEF348N
Revision: December 20092009 QX56
PRECAUTIONSHA-9
< PRECAUTION >
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*: Always check with the Parts Department for the latest parts information.
WARNING:
Make sure all refrigerant is discharged into the recycling equipment and the pressure in the system is
less than atmospheric pressure. Then gradually loo sen the discharge side hose fitting and remove it.
CAUTION:
When replacing or cleaning refrigerant cycle components, observe the following.
When the compressor is removed, st ore it in the same position as it is when mounted on the car.
Failure to do so will cause oil to enter the low pressure chamber.
When connecting tubes, always use a to rque wrench and a back-up wrench.
After disconnecting tubes, immediately plug all op enings to prevent entry of dirt and moisture.
When installing an air conditioner in the vehicle, connect the pipes as the final stage of the opera-
tion. Do not remove the seal caps of pipes and other components until just before required for con-
nection.
Allow components stored in cool areas to warm to working area temperature before removing seal
caps. This prevents condensation from forming inside A/C components.
Thoroughly remove moisture from the refriger ation system before charging the refrigerant.
Always replace used O-rings.
When connecting tube, apply oil to circle of the O-ri ngs shown in illustration. Be careful not to apply
oil to threaded portion.
Oil name: NISSAN A/C System Oil Type S or equivalent
O-ring must be closely attached to dented portion of tube.
When replacing the O-ring, be careful not to damage O-ring and tube.
Connect tube until you hear it cl ick, then tighten the nut or bolt by hand until snug. Make sure that
the O-ring is installed to tube correctly.
After connecting line, conduct leak test and make sure that there is no leakage from connections.
When the gas leaking point is f ound, disconnect that line and replace the O-ring. Then tighten con-
nections of seal seat to the specified torque.
Connec-
tion type O-ring
size Part number* D mm (in) W mm (in)
New 8 92471 N8210 6.8 (0.268) 1.85 (0.0728)
Former 10 J2476 89956 9.25 (0.3642) 1.78 (0.0701) New 1292472 N8210 10.9 (0.429) 2.43 (0.0957)
Former 92475 71L00 11.0 (0.433) 2.4 (0.094) New 1692473 N8210 13.6 (0.535) 2.43 (0.0957)
Former 92475 72L00 14.3 (0.563) 2.3 (0.091) New 1992474 N8210 16.5 (0.650) 2.43 (0.0957)
Former 92477 N8200 17.12 (0.6740) 1.78 (0.0701) New 24 92195 AH300 21.8 (0.858) 2.4 (0.094)
SHA814E
Revision: December 20092009 QX56
HA-22
< ON-VEHICLE MAINTENANCE >
OIL
OIL
Maintenance of Oil Quantity in CompressorINFOID:0000000003775302
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 replacedOil 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
Revision: December 20092009 QX56