2011 INFINITI QX56 Fuel

EC-488
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P2A00, P2A03 A/F SENSOR 1
3. Listen for an intake air leakage after the mass air flow sensor.
Is intake air leakage detected?
YES >> Repair or replace malfunctioning part.
NO >> GO TO 4.
4.CLEAR THE MIXTURE RATIO SELF-LEARNING VALUE
1. Clear the mixture ratio self-learning value. Refer to EC-152, "
Work Procedure".
2. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171, P0172, P0174 or P 0175 detected? Is it difficult to start engine?
YES >> Perform trouble diagnosis for DTC P0171, P0174 or P0172, P0175. Refer to EC-264, "Diagnosis
Procedure" or EC-268, "Diagnosis Procedure".
NO >> GO TO 5.
5.CHECK AIR FUEL RATIO SENSOR 1 POWER SUPPLY CIRCUIT
1. Disconnect air fuel ratio (A/F) sensor 1 harness connector.
2. Turn ignition switch ON.
3. Check the voltage between A/F sensor 1 harness connector and ground.
Is the inspection result normal?
YES >> GO TO 6.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
6.CHECK A/F SENSOR 1 INPUT SIGN AL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between A/F sensor 1 harness connector and ECM harness connector.
4. Check the continuity between A/F sensor 1 harness connector and ground, or ECM harness connector
and ground.
5. Also check harness for short to power.
Is the inspection result normal?
YES >> GO TO 7.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
7.CHECK A/F SENSOR 1 GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between A/F sensor 1 harness connector and ECM harness connector.
DTCA/F sensor 1
Ground Voltage
Bank Connector Terminal
P2A00 1 F67 4 Ground 3.0 V
P2A03 2 F68 4
DTC A/F sensor 1 ECM
Continuity
Bank Connector Terminal Connector Terminal
P2A00 1 F67 3 F11088
Existed
P2A03 2 F68 3 78
DTC A/F sensor 1 ECM
Ground Continuity
Bank Connector Terminal Connector Terminal
P2A00 1 F67 3 F11088
Ground Not existed
P2A03 2 F68 3 78
Revision: 2010 May2011 QX56

P2A00, P2A03 A/F SENSOR 1EC-489
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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4. Also check harness for short to power.
Is the inspection result normal?
YES >> GO TO 8.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
8.CHECK A/F SENSOR 1 HEATER
Refer to EC-182, "
Component Inspection (A/F Sensor 1 Heater)".
Is the inspection result normal?
YES >> GO TO 9.
NO >> GO TO 10.
9.CHECK INTERMITTENT INCIDENT
Perform GI-40, "
Intermittent Incident".
Is the inspection result normal?
YES >> GO TO 10.
NO >> Repair or replace malfunctioning part.
10.REPLACE AIR FUEL RATIO (A/F) SENSOR 1
Replace air fuel ratio (A/F) sensor 1. Refer to EX-5, "
Exploded View".
CAUTION:
 Discard any A/F sensor which has been dropped from a height of more than 0.5 m (19.7 in) onto a
hard surface such as a concrete floor; use a new one.
 Before installing new A/F senso r, clean exhaust system threads using Oxygen Sensor Thread
Cleaner [commercial service tool (J-43897-18 or J-43897-12)] and approved anti-seize lubricant
(commercial service tool).
Will CONSULT-III be used?
YES >> GO TO 11.
NO >> GO TO 12.
11 .CONFIRM A/F ADJUSTMENT DATA
WITH CONSULT-III
1. Turn ignition switch ON.
2. Select “A/F ADJ-B1” and “A/F ADJ-B2” in “DATA MONITOR” mode with CONSULT-III.
3. Check that “0.000” is di splayed on CONSULT-III screen.
Is
“0.000” displayed?
YES >> INSPECTION END
NO >> GO TO 12.
12.CLEAR THE MIXTURE RATIO SELF-LEARNING VALUE
Clear the mixture ratio self-learning value. Refer to EC-152, "
Work Procedure".
Will CONSULT-III be used?
YES >> GO TO 13.
NO >> INSPECTION END
13.CONFIRM A/F ADJUSTMENT DATA
WITH CONSULT-III
1. Turn ignition switch ON.
2. Select “A/F ADJ-B1” and “A/F ADJ-B2” in “DATA MONITOR” mode with CONSULT-III.
3. Check that “0.000” is di splayed on CONSULT-III screen.
>> INSPECTION END
DTC A/F sensor 1 ECM
Continuity
Bank Connector Terminal Connector Terminal
P2A00 1 F67 6 F11094
Existed
P2A03 2 F68 6 74
Revision: 2010 May2011 QX56

EC-498
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
FUEL INJECTOR
FUEL INJECTOR
Component Function CheckINFOID:0000000006218002
1.INSPECTION START
Turn ignition switch to START.
Are any cylinders ignited?
YES >> GO TO 2.
NO >> Proceed to EC-498, "
Diagnosis Procedure".
2.CHECK FUEL INJECTOR FUNCTION
WITH CONSULT-III
1. Start engine.
2. Perform “POWER BALANCE” in “A CTIVE TEST” mode with CONSULT-III.
3. Check that each circuit produces a momentary engine speed drop.
WITHOUT CONSULT-III
1. Start engine.
2. Listen to each fuel injector operating sound.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Proceed to EC-498, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000006218003
1.CHECK FUEL INJECTOR POWER SUPPLY
1. Turn ignition switch ON.
2. Check the voltage between ECM harness connector and ground.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Perform the trouble diagnosis for power supply circuit. Refer to EC-168, "
Diagnosis Procedure".
2.CHECK FUEL INJECTOR CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect fuel injector harness connector and ECM harness connector.
3. Check the continuity between fuel inje ctor harness connector and ECM harness connector.
Clicking sound should be heard.
PBIB3332E
+
−Voltag e
ECM
Connector Terminal
F 111 46
Ground Battery voltage
51
E80 111
11 2
Revision: 2010 May2011 QX56

FUEL INJECTOREC-499
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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4. Also check harness for short to ground and to power.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair or replace error-detected parts.
3.CHECK ECM GROUND CIRCUIT
Check the continuity between ECM harness connector and ground.
Is inspection result normal?
YES >> GO TO 4.
NO >> Repair or replace error-detected parts.
4.CHECK FUEL INJECTOR
Refer to EC-499, "
Component Inspection".
Is the inspection result normal?
YES >> Check intermittent incident. Refer to GI-40, "Intermittent Incident".
NO >> Replace malfunctioning fuel injector. Refer to EM-49, "
Removal and Installation".
Component InspectionINFOID:0000000006218004
1.CHECK FUEL INJECTOR
1. Turn ignition switch OFF.
2. Disconnect fuel injector harness connector.
3. Check the resistance between fuel injector terminals as per the following.
Cylinder +
−
Continuity
Fuel injector ECM
Connector Terminal Connector Terminal
1F123 1
F110 101
Existed
2108
2F124 1
F 111 7
24
3F125 1
F 111 6
23
4F126 1
F110 107
2104
5F127 1
F 111 2
29
6F128 1
F110 102
2109
7F129 1
F110 106
2103
8F130 1
F 111 1
28
+ −Continuity
ECM
Connector Terminal F 111 5 Ground Exsisted
E80 11 4
11 5
Revision: 2010 May2011 QX56

EC-500
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
FUEL INJECTOR
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace malfunctioning fuel injector. Refer to
EM-49, "
Removal and Installation".
Injector
Condition Resistance
+ −
Te r m i n a l
1 2 Temperature 10 - 60 °C (50 - 140 °F) 1.44 - 1.73 Ω
Revision: 2010 May2011 QX56

HIGH PRESSURE FUEL PUMPEC-501
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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HIGH PRESSURE FUEL PUMP
Component Function CheckINFOID:0000000006218005
1.CHECK HIGH PRESSURE FUEL PUMP FUNCTION
WITH CONSULT-III
1. Start engine.
2. Check “FUEL PRES SEN V” in “D ATA MONITOR” mode with CONSULT-III.
WITHOUT CONSULT-III
1. Start engine.
2. Check the voltage between ECM harness connector and ground.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Proceed to EC-501, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000006218006
1.CHECK HIGH PRESSURE FUEL PUMP SOLENOID CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector and high pressure fuel pump harness connector.
3. Check the continuity between ECM harness connector and high pressure fuel pump harness connector.
Monitor Item Condition Values/Status
FUEL PRES SEN V Engine speed: Idle 980 – 1,200 mV
Engine speed: Revving engine from idle to 4,000 rpm
quickly
1,100 – 2,900 mV
ECM
Condition Voltage
+ −
Connector Terminal Connector Terminal
F110 105 E80 175 [Engine is running]
 Warm-up condition
 Idle speed
NOTE:
The pulse cycle changes depending
on rpm at idle BATTERY VOLTAGE
(11 - 14 V)
[Engine is running]
 Warm-up condition
 Engine speed: 2,000 rpm BATTERY VOLTAGE
(11 - 14 V)
JPBIA3340ZZ
JPBIA3341ZZ
+
−
Continuity
ECM High pressure fuel pump
Connector Terminal Connector Terminal
F110 105
F24 1
Existed
11 0 2
Revision: 2010 May2011 QX56

EC-502
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
HIGH PRESSURE FUEL PUMP
4. Also check harness for short to ground and to power.
Is inspection result normal?
YES >> GO TO 2.
NO >> Repair or replace error-detected parts.
2.CHECK HIGH PRESSURE
FUEL PUMP SOLENOID
Refer to EC-502, "
Component Inspection".
Is inspection result normal?
YES >> GO TO 3.
NO >> Replace high pressure fuel pump. Refer to EM-43, "
Removal and Installation".
3.CHECK HIGH PRESSURE FUEL PUMP INSTALLATION CONDITION
1. Turn ignition switch OFF.
2. Check that the high pressure fuel pump is installed with no backlash and looseness.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair or replace error-detected parts.
4.CHECK CAMSHAFT
1. Remove camshaft. Refer to EM-75, "
Removal and Installation".
2. Check camshaft. Refer to EM-77, "
Inspection".
Is inspection result normal?
YES >> INSPECTION END
NO >> Replace camshaft. Refer to EM-75, "
Removal and Installation".
Component InspectionINFOID:0000000006218007
1.CHECK HIGH PRESSURE FUEL PUMP SOLENOID
1. Turn ignition switch OFF.
2. Disconnect high pressure fuel pump harness connector.
3. Check the resistance between high pressure fuel pump connector terminals as per the following.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace high pressure fuel pump. Refer to EM-43, "
Removal and Installation".
+−
Condition Resistance
High pressure fuel pump
Te r m i n a l
1 2 Temperature 20 – 30 °C (68 – 86 °F) 9 – 11 Ω
Revision: 2010 May2011 QX56

EC-510
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
IGNITION SIGNAL
3. Remove fuel pump fuse in IPDM E/R to release fuel pressure.
NOTE:
 For the fuse number, refer to EC-114, "
Wiring Diagram".
 For the fuse arrangement, refer to PG-143, "
Fuse, Connector and Terminal Arrangement".
 Do not use CONSULT-III to release fuel pressure , or fuel pressure applies again during the following
procedure.
4. Start engine.
5. After engine stalls, crank it 2 or 3 times to release all fuel pressure.
6. Turn ignition switch OFF.
7. Remove all ignition coil harness connectors to avoi d the electrical discharge from the ignition coils.
8. Remove ignition coil and spark plug of the cylinder to be checked.
9. Crank engine for 5 seconds or more to remove combustion gas in the cylinder.
10. Connect spark plug and harness connector to ignition coil.
11. Fix ignition coil using a rope etc. with gap of 13 - 17 mm (0.52 - 0.66 in) between the edge of the spark plug and grounded metal
portion as shown in the figure.
12. Crank engine for approximately 3 seconds, and check whether
spark is generated between the spark plug and the grounded
metal portion.
CAUTION:
 Never place the spark plug and the ignition coil within 50
cm (19.7 in) each other. Be careful not to get an electrical
shock while checking, becau se the electrical discharge
voltage becomes 20 kV or more.
 It might damage the ignition coil if the gap of more than 17 mm (0.66 in) is made.
NOTE:
When the gap is less than 13 mm (0.52 in), a spark might be generated even if the coil is malfunc-
tioning.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace malfunctioning ignition coil with power transistor.
Component Inspection (Condenser)INFOID:0000000006218014
1.CHECK CONDENSER
1. Turn ignition switch OFF.
2. Disconnect condenser harness connector.
3. Check resistance between condenser terminals as per the following.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace condenser. Spark should be generated.
JMBIA0066GB
Terminals Resistance
1 and 2 Above 1 M Ω [at 25 °C (77 °F)]
Revision: 2010 May2011 QX56