2011 INFINITI QX56 engine

EC-358
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0506 ISC SYSTEM
P0506 ISC SYSTEM
DescriptionINFOID:0000000006217861
The ECM controls the engine idle speed to a specified leve
l through the fine adjustment of the air, which is let
into the intake manifold, by operating the electric thrott le control actuator. The operating of the throttle valve is
varied to allow for optimum control of the engine idli ng speed. The crankshaft position sensor detects the
actual engine speed and sends a signal to the ECM.
The ECM controls the electric throttle control actuator so that the engine speed coincides with the target value
memorized in the ECM. The target engine speed is t he lowest speed at which the engine can operate steadily.
The optimum value stored in the ECM is determined by taking into consideration various engine conditions,
such as during warming up, deceleration and engine load (air conditioner, power steering and cooling fan
operation, etc.).
DTC LogicINFOID:0000000006217862
DTC DETECTION LOGIC
NOTE:
If DTC P0506 is displayed with ot her DTC, first perform the trouble diagnosis for the other DTC.
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
If the target idle speed is ou t of the specified value, perform EC-148, "
Work Procedure", before con-
ducting DTC Confirmation Procedure.
TESTING CONDITION:
 Before performing the following procedure, confirm that battery voltage is 11 V or more at idle.
 Always perform the test at a temperature above −10 °C (14 °F).
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Restart engine and run it for at least 1 minute at idle speed.
6. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-358, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217863
1.CHECK INTAKE AIR LEAKAGE
1. Start engine and let it idle.
2. Listen for an intake air leakage after the mass air flow sensor.
Is intake air leakage detected?
YES >> Discover air leakage location and repair.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0506 ISC SYSTEM
(Idle speed control system
RPM lower than expected) The idle speed is less than the target idle
speed by 100 rpm or more.
 Electric throttle control actuator
 Intake air leakage
Revision: 2010 May2011 QX56

P0506 ISC SYSTEMEC-359
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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NO >> GO TO 2.
2.REPLACE ECM
1. Stop engine.
2. Replace ECM.
3. Perform additional service when replacing ECM. Refer to EC-143, "
Work Procedure".
>> INSPECTION END
Revision: 2010 May2011 QX56

EC-360
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0507 ISC SYSTEM
P0507 ISC SYSTEM
DescriptionINFOID:0000000006217864
The ECM controls the engine idle speed to a specified leve
l through the fine adjustment of the air, which is let
into the intake manifold, by operating the electric thrott le control actuator. The operating of the throttle valve is
varied to allow for optimum control of the engine idli ng speed. The crankshaft position sensor detects the
actual engine speed and sends a signal to the ECM.
The ECM controls the electric throttle control actuator so that the engine speed coincides with the target value
memorized in the ECM. The target engine speed is t he lowest speed at which the engine can operate steadily.
The optimum value stored in the ECM is determined by taking into consideration various engine conditions,
such as during warming up, deceleration and engine load (air conditioner, power steering and cooling fan
operation, etc.).
DTC LogicINFOID:0000000006217865
DTC DETECTION LOGIC
NOTE:
If DTC P0507 is displayed with ot her DTC, first perform the trouble diagnosis for the other DTC.
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
If the target idle speed is ou t of the specified value, perform EC-148, "
Work Procedure", before con-
ducting DTC Confirmation Procedure.
TESTING CONDITION:
 Before performing the following procedure, confirm that battery voltage is 11 V or more at idle.
 Always perform the test at a temperature above −10 °C (14 °F).
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Start engine and run it for at least 1 minute at idle speed.
6. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-360, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217866
1.CHECK PCV HOSE CONNECTION
Confirm that PCV hose is connected correctly.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair or replace malfunctioning part.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0507 ISC SYSTEM
(Idle speed control system
RPM higher than expected) The idle speed is more than the target idle
speed by 200 rpm or more.  Electric throttle control actuator
 Intake air leakage
 PCV system
Revision: 2010 May2011 QX56

P0507 ISC SYSTEMEC-361
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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2.CHECK INTAKE AIR LEAKAGE
1. Start engine and let it idle.
2. Listen for an intake air leakage after the mass air flow sensor.
Is intake air leakage detected?
YES >> Discover air leakage location and repair.
NO >> GO TO 3.
3.REPLACE ECM
1. Stop engine.
2. Replace ECM.
3. Perform additional service when replacing ECM. Refer to EC-143, "
Work Procedure".
>> INSPECTION END
Revision: 2010 May2011 QX56

EC-362
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P050E COLD START CONTROL
P050E COLD START CONTROL
DescriptionINFOID:0000000006288336
ECM controls ignition timing and engine idle speed when engine is started with pre-warming up condition.
This control promotes the activation of three way ca
talyst by heating the catalyst and reduces emissions.
DTC LogicINFOID:0000000006288337
DTC DETECTION LOGIC
NOTE:
If DTC P050E is displayed with other DTC, first perform the trouble diagnosis for other DTC.
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is 11 V or more at idle.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE-I
WITH CONSULT-III
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Select “DATA MONITOR” mode with CONSULT-III.
4. Check the indication of “COOLAN TEMP/S”.
WITH GST
Follow the procedure “With CONSULT-III” above.
Is the value of
“COOLAN TEMP/S” between 5°C (41°F) and 36°C (97°F)?
YES >> GO TO 3.
NO-1 [If it is below 5 °C (41 °F)]>>Warm up the engine until the val ue of “COOLAN TEMP/S” reaches 5°C
(41 °F) or more. Retry from step 1.
NO-2 [If it is above 36 °C (97 °F)]>>Cool engine down to less than 36 °C (97 °F). Retry from step 1.
3.PERFORM DTC CONFIRMATION PROCEDURE-II
WITH CONSULT-III
1. Set the select lever in N range.
2. Start the engine and warm up in idle with the value of “COOLAN TEMP/S” between 5 °C (41 °F) and 40 °C
(104 °F) for more than 15 seconds.
3. Check 1st trip DTC.
WITH GST
Follow the procedure “With CONSULT-III” above.
Is 1st trip DTC detected?
YES >> Proceed to EC-362, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006288338
1.PERFORM IDLE AIR VOLUME LEARNING
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P050E Cold start engine exhaust temper-
ature too low The temperature of the catalyst inlet does not
rise to the proper temperature when the engine
is started with pre-warming up condition.  Lack of intake air volume
 Fuel injection system
ECM
Revision: 2010 May2011 QX56

EC-364
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0524 ENGINE OIL PRESSURE
P0524 ENGINE OIL PRESSURE
DTC LogicINFOID:0000000006288342
DTC DETECTION LOGIC
NOTE:
If DTC P0524 is displayed with DTC P0075 or P0081,
perform trouble diagnosis for DTC P0075 or P0081
first. Refer to EC-193, "
DTC Logic".
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING-I
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confi rm that battery voltage is between 10 V and 16 V at
idle.
>> GO TO 2.
2.PRECONDITIONING-II
Check oil level and oil pressure. Refer to LU-7, "
Inspection".
Is the inspection result normal?
YES >> GO TO 3.
NO >> Proceed to LU-7, "
Inspection".
3.PERFORM DTC CONFIRMATION PROCEDURE
WITH CONSULT-III
1. Select “DATA MONITOR” mode with CONSULT-III.
2. Maintain the following conditions for at least 20 consecutive seconds.
CAUTION:
Always drive at a safe speed.
3. Check 1st trip DTC.
WITH GST
Follow the procedure “With CONSULT-III” above.
Is 1st trip DTC detected?
YES >> Proceed to EC-365, "Diagnosis Procedure"
DTC No.Trouble diagnosis name
(Trouble diagnosis content) Detecting condition Possible cause
P0524 ENGINE OIL PRESSURE
(Engine oil pressure too low) Engine oil pressure is low because
there is a gap between angle of target
and phase-control angle.  Engine oil pressure or level too low
 Crankshaft position sensor
 Camshaft position sensor
 Intake valve timing control solenoid valve
 Accumulation of debris to the signal pick-up por-
tion of the camshaft
 Timing chain installation
 Foreign matter caught in the oil groove for intake valve timing control
ENG SPEED More than 1,700 rpm
COOLAN TEMP/S More than 70 °C (158 °F)
Selector lever 1st or 2nd position
Driving location uphill Driving vehicle uphill
(Increased engine load will help maintain the driving
conditions required for this test.)
Revision: 2010 May2011 QX56

P0524 ENGINE OIL PRESSUREEC-365
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006288343
1.CHECK OIL PRESSURE WARNING LAMP
1. Start engine.
2. Check oil pressure warning lamp and confirm it is not illumi- nated.
Is oil pressure warning lamp illuminated?
YES >> Proceed to LU-7, "Inspection".
NO >> GO TO 2.
2.CHECK INTAKE VALVE TIMING CONTROL SOLENOID VALVE
Refer to EC-179, "
Component Inspection (Intake Valve Timing Control Solenoid Valve)".
Is the inspection result normal?
YES >> GO TO 3.
NO >> Replace malfunctioning intake valve timing control solenoid valve.
3.CHECK CRANKSHAFT POSITION SENSOR
Refer to EC-301, "
Component Inspection (Crankshaft Position Sensor)".
Is the inspection result normal?
YES >> GO TO 4.
NO >> Replace crankshaft position sensor.
4.CHECK CAMSHAFT PO SITION SENSOR
Refer to EC-306, "
Component Inspection (Camshaft Position Sensor)".
Is the inspection result normal?
YES >> GO TO 5.
NO >> Replace malfunctioning camshaft position sensor.
5.CHECK CAMSHAFT SPROCKET (SIGNAL PLATE)
Check the following.
 Accumulation of debris to the signal plate of camshaft sprocket (INT)
 Chipping signal plate of camshaft sprocket (INT)
Is the inspection result normal?
YES >> GO TO 6.
NO >> Remove debris and clean the signal plate of camshaft sprocket (INT) or replace camshaft sprocket (INT).
Refer to EM-61, "
Exploded View".
6.CHECK TIMING CHAIN INSTALLATION
Check service records for any recent repairs that may cause timing chain misaligned.
Are there any service records that may cause timing chain misaligned?
YES >> Check timing chain installation. Refer to EM-61, "Exploded View".
NO >> GO TO 7.
7.CHECK LUBRICATION CIRCUIT
Perform “Inspection of Camshaft Sprocket (INT) Oil Groove”. Refer to LU-7, "
Inspection".
PBIA8559J
JMBIA0962ZZ
Revision: 2010 May2011 QX56

EC-366
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0524 ENGINE OIL PRESSURE
Is the inspection result normal?
YES >> GO TO 8.
NO >> Clean lubrication line.
8.CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
>> INSPECTION END
Revision: 2010 May2011 QX56