engine INFINITI QX56 2010 Factory Service Manual

EC-382
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P2A00, P2A03 A/F SENSOR 1
P2A00, P2A03 A/F SENSOR 1
Component DescriptionINFOID:0000000005149460
The air fuel ratio (A/F) sensor 1 is a planar one-cell limit current sen-
sor. The sensor element of the
A/F sensor 1 is composed an elec-
trode layer, which transports ions. It has a heater in the element.
The sensor is capable of precise measurement = 1, but also in the
lean and rich range. Together with its control electronics, the sensor
outputs a clear, continuous signal throughout a wide range.
The exhaust gas components diffuse through the diffusion layer at
the sensor cell. An electrode layer is applied voltage, and this current
relative oxygen density in lean. Also this current relative hydrocar-
bon density in rich.
Therefore, the A/F sensor 1 is able to indicate air fuel ratio by this
electrode layer of current. In addition, a heater is integrated in the
sensor to ensure the required operating temperature of about 800° C
(1,472° F).
On Board Diagn osis LogicINFOID:0000000005149461
To judge the malfunction, the A/F signal computed by ECM from the A/F sensor 1 signal is monitored not to be
shifted to LEAN side or RICH side.
DTC Confirmation ProcedureINFOID:0000000005149462
NOTE:
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure
before conducting the next step.
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 more than 11 V at idle.
WITH CONSULT-III
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 and select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CON-
SULT-III.
4. Clear the self-learning coef ficient by touching “CLEAR”.
PBIB3353E
PBIB3354E
DTC No. Trouble diagnosis name DTC detecting conditionPossible Cause
P2A00
2A00
(Bank 1) Air fuel ratio (A/F) sensor 1
circuit range/performance • The output voltage computed by ECM from the
A/F sensor 1 signal is shifted to the lean side for
a specified period.
• The A/F signal computed by ECM from the A/F
sensor 1 signal is shifted to the rich side for a
specified period. • A/F sensor 1
• A/F sensor 1 heater
• Fuel pressure
• Fuel injector
• Intake air leaks
P2A03
2A03
(Bank 2)
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P2A00, P2A03 A/F SENSOR 1EC-383
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5. Turn ignition switch OFF and wait at least 10 seconds.
6. Start engine and keep the engine speed between 3,500 and 4,000 rpm for 1 minute under no load.
7. Let engine idle for 1 minute.
8. Keep engine speed between 2,500 and 3,000 rpm for 20 minutes.
9. Check 1st trip DTC.
10. If 1st trip DTC is detected, go to
EC-383, "
Diagnosis Procedure".
WITH GST
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Disconnect mass air flow sensor harness connector.
4. Start engine and let it idle for at least 5 seconds.
5. Stop engine and reconnect mass air flow sensor harness con-
nector.
6. Select Service $03 with GST and make sure that DTC P0102 is detected.
7. Select Service $04 with GST and erase the DTC P0102.
8. Start engine and keep the engine speed between 3,500 and 4,000 rpm for 1 minute under no load.
9. Let engine idle for 1 minute.
10. Keep engine speed between 2,500 and 3,000 rpm for 20 min- utes.
11. Select Service $07 with GST. If 1st trip DTC is detected, go to EC-383, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000005149463
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten two ground screws on the body. Refer to EC-85, "
Ground Inspection".
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2.RETIGHTEN A/F SENSOR 1
BBIA0368E
BBIA0354E
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EC-384
< COMPONENT DIAGNOSIS >[VK56DE]
P2A00, P2A03 A/F SENSOR 1
1. Loosen and retighten the A/F sensor 1.
>> GO TO 3.
3.CHECK FOR INTAKE AIR LEAK
1. Start engine and run it at idle.
2. Listen for an intake air leak after the mass air flow sensor.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace.
4.CLEAR THE SELF-LEARNING DATA
With CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CONSULT-III.
3. Clear the self-learning control coefficient by touching “CLEAR”.
4. Run engine for at least 10 minutes at idle speed. Is the 1st trip DTC P0171, P0172, P0174 or P0175 detected?
Is it difficult to start engine?
Without CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF.
3. Disconnect mass air flow sensor harness connector.
4. Restart engine and let it idle for at least 5 seconds.
5. Stop engine and reconnect mass air flow sensor harness con- nector.
6. Make sure DTC P0102 is displayed.
7. Erase the DTC memory. Refer to EC-459, "
DTC Index".
8. Make sure DTC P0000 is displayed.
9. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171, P0172, P0174 or P0175 detected?
Is it difficult to start engine?
Ye s o r N o
Yes >> Perform trouble diagnosis for DTC P0171, P0174 or P0172, P0175. Refer to EC-172
or EC-177.
No >> GO TO 5.
5.CHECK HARNESS CONNECTOR
1. Turn ignition switch OFF. Tightening torque: 50 N-m (5.1 kg-m, 37 ft-lb)
BBIA0375E
BBIA0368E
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EC-386
< COMPONENT DIAGNOSIS >[VK56DE]
P2A00, P2A03 A/F SENSOR 1
5. Also check harness for short to power.
OK or NG
OK >> GO TO 9.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
9.CHECK A/F SENSOR 1 HEATER
Refer to EC-97, "
Component Inspection".
OK or NG
OK >> GO TO 10.
NG >> GO TO 11.
10.CHECK INTERMITTENT INCIDENT
Perform GI-35, "
How to Check Terminal" and GI-38, "Intermittent Incident".
OK or NG
OK >> GO TO 11.
NG >> Repair or replace.
11 .REPLACE AIR FUEL RATIO (A/F) SENSOR 1
Replace malfunctioning air fuel ratio (A/F) sensor 1.
CAUTION:
• Discard any A/F sensor which has been dropped from a height of more than 0.5 m (1.6 ft) onto a hard surface such as a concrete floor; use a new one.
• Before installing new A/F sensor, clean exhau st system threads using Oxygen Sensor Thread
Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.
>> GO TO 12.
12.CONFIRM A/F ADJUSTMENT DATA
1. Turn ignition switch OFF and then ON.
2. Select “A/F ADJ-B1” and “” in “D ATA MONITOR” mode with CONSULT-III.
3. Make sure that “0.000” is displayed on CONSULT-III screen.
OK or NG
OK >> INSPECTION END
NG >> GO TO 13.
13.CLEAR THE SELF-LEARNING DATA
With CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CONSULT-III.
3. Clear the self-learning control coefficient by touching “CLEAR”.
Without CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF.
Bank 1 Bank 2
A/F sensor 1 terminal ECM terminal A/F sensor 1 terminal ECM terminal 13 511 6
25 627 5
Continuity should not exist.
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P2A00, P2A03 A/F SENSOR 1EC-387
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3. Disconnect mass air flow sensor harness connector.
4. Restart engine and let it idle for at least 5 seconds.
5. Stop engine and reconnect mass air flow sensor harness con-
nector.
6. Make sure DTC P0102 is displayed.
7. Erase the DTC memory. Refer to EC-55, "
Malfunction Indicator
Lamp (MIL)".
8. Make sure DTC P0000 is displayed.
>> GO TO 14.
14.CONFIRM A/F ADJUSTMENT DATA
1. Turn ignition switch OFF and then ON.
2. Select “A/F ADJ-B1” and “A/F ADJ-B2” in “DATA MONITOR” mode with CONSULT-III.
3. Make sure that “0.000” is displayed on CONSULT-III screen.
>>INSPECTION END
BBIA0368E
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EC-396
< COMPONENT DIAGNOSIS >[VK56DE]
FUEL INJECTOR
FUEL INJECTOR
Component DescriptionINFOID:0000000005149473
The fuel injector is a small, precise solenoid valve. When the ECM
supplies a ground to the fuel injector circuit, the coil in the fuel injec-
tor is energized. The energized coil pulls the ball valve back and
allows fuel to flow through the fuel injector into the intake manifold.
The amount of fuel injected depends upon the injection pulse dura-
tion. Pulse duration is the length of time the fuel injector remains
open. The ECM controls the injection pulse duration based on
engine fuel needs.
Diagnosis ProcedureINFOID:0000000005149474
1.INSPECTION START
Turn ignition switch to START.
Is any cylinder ignited?
Ye s o r N o
Ye s > > G O T O 2 .
No >> GO TO 3.
2.CHECK OVERALL FUNCTION
With CONSULT-III
1. Start engine.
2. Perform “POWER BALANCE” in “A CTIVE TEST” mode with CONSULT-III.
3. Make sure that each circuit produces a momentary engine speed drop.
Without CONSULT-III
1. Start engine.
2. Listen to each fuel injector operating sound.
Clicking noise should be heard.
OK or NG
OK >> INSPECTION END
NG >> GO TO 3.
3.CHECK FUEL INJECTOR POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
SEF375Z
PBIB1986E
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FUEL PUMPEC-399
< COMPONENT DIAGNOSIS > [VK56DE]
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FUEL PUMP
DescriptionINFOID:0000000005149476
SYSTEM DESCRIPTION
*: ECM determines the start signal status by the signals of engine speed and battery voltage.
The ECM activates the fuel pump for several seconds after the ignition switch is turned ON to improve engine
startability. If the ECM receives a engine speed signal
from the camshaft position sensor (PHASE), it knows
that the engine is rotating, and causes the pump to operate. If the engine speed signal is not received when
the ignition switch is ON, the engine stalls. The EC M stops pump operation and prevents battery discharging,
thereby improving safety. The ECM does not directly dr ive the fuel pump. It controls the ON/OFF fuel pump
relay, which in turn controls the fuel pump.
COMPONENT DESCRIPTION
A turbine type design fuel pump is used in the fuel tank.
Diagnosis ProcedureINFOID:0000000005149477
1.CHECK OVERALL FUNCTION
1. Turn ignition switch ON.
2. Pinch fuel feed hose with two fingers.
OK or NG
OK >> INSPECTION END
NG >> GO TO 2.
2.CHECK FUEL PUMP POWER SUPPLY CIRCUIT-I
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Turn ignition switch ON.
Sensor Input signal to ECMECM FunctionActuator
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE) Engine speed*
Fuel pump control Fuel pump relay
Battery Battery voltage*
Condition Fuel pump operation
Ignition switch is turned to ON. Operates for 1 second.
Engine running and cranking Operates.
When engine is stopped Stops in 1.5 seconds.
Except as shown above Sto ps .
BBIA0402E
Fuel pressure pulsation should be felt on the fuel feed
hose for 1 second after ignition switch is turned ON.
BBIA0357E
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IGNITION SIGNALEC-407
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IGNITION SIGNAL
Component DescriptionINFOID:0000000005149482
IGNITION COIL & POWER TRANSISTOR
The ignition signal from the ECM is sent to and amplifi
ed by the power transistor. The power transistor turns
ON and OFF the ignition coil primary circuit. This ON/OFF operation induces the proper high voltage in the coil
secondary circuit.
Diagnosis ProcedureINFOID:0000000005149483
1.CHECK ENGINE START
Turn ignition switch OFF, and restart engine.
Is engine running?
Ye s o r N o
Yes (With CONSULT-III)>>GO TO 2.
Yes (Without CONSULT-III)>>GO TO 3.
No >> GO TO 4.
2.CHECK OVERALL FUNCTION
With CONSULT-III
1. Perform “POWER BALANCE” in “A CTIVE TEST” mode with CONSULT-III.
2. Make sure that each circuit produces a momentary engine speed drop.
OK or NG
OK >> INSPECTION END
NG >> GO TO 10.
3.CHECK OVERALL FUNCTION
Without CONSULT-III
1. Let engine idle.
2. Read the voltage signal between ECM terminals 46, 60, 61, 62, 65, 79, 80, 81 and ground with an oscilloscope.
3. Verify that the oscilloscope screen shows the signal wave as shown below.
NOTE:
The pulse cycle changes depending on rpm at idle.
OK or NG
1. Ignition coils (with power transistor) (bank 2) 2. Ignition coils (with power transistor)
(bank 1)
BBIA0777E
PBIB2094E
PBIB0044E
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IGNITION SIGNALEC-411
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7. Remove fuel pump fuse in IPDM E/R to release fuel pressure.
NOTE:
Do not use CONSULT-III to release fuel pressure, or fuel pres-
sure applies again during the following procedure.
8. Start engine.
9. After engine stalls, crank it two or three times to release all fuel pressure.
10. Turn ignition switch OFF.
11. Remove all ignition coil harness connectors to avoid the electri- cal discharge from the ignition coils.
12. Remove ignition coil and spark plug of the cylinder to be checked.
13. Crank engine for 5 seconds or more to remove combustion gas in the cylinder.
14. Connect spark plug and harness connector to ignition coil.
15. 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.
16. Crank engine for about 3 seconds, and check whether spark is generated between the spark plug and the grounded metal por-
tion.
CAUTION:
• Do not approach to the spark plug and the ignition coil
within 50cm. Be careful not to get an electrical shock
while checking, because the el ectrical discharge voltage
becomes 20kV or more.
• It might cause to damage the ignition coil if the gap of more than 17 mm (0.66 in) is taken.
NOTE:
When the gap is less than 13 mm (0.52 in), the sp ark might be generated even if the coil is mal-
functioning.
17. If NG, replace ignition coil with power transistor.
CONDENSER-1
1. Turn ignition switch OFF.
2. Disconnect condenser-1 harness connector.
3. Check resistance between condenser-1 terminals 1 and 2. Spark should be generated.
BBIA0380E
PBIB2325E
Resistance
Above 1 MΩ [at 25 °C (77 °F)]
PBIB0794E
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EC-412
< COMPONENT DIAGNOSIS >[VK56DE]
ON BOARD REFUELING VAPOR RECOVERY (ORVR)
ON BOARD REFUELING VAPOR RECOVERY (ORVR)
System DescriptionINFOID:0000000005149485
From the beginning of refueling, the air and vapor insi
de the fuel tank go through refueling EVAP vapor cut
valve and EVAP/ORVR line to the EVAP canister. The vapor is absorbed by the EVAP canister and the air is
released to the atmosphere.
When the refueling has reached the full level of the fuel tank, the refueling EVAP vapor cut valve is closed and
refueling is stopped because of auto shut-off. The vapor which was absorbed by the EVAP canister is purged
during driving.
WARNING:
When conducting inspections below, be sure to observe the following:
• Put a “CAUTION: FLAMMABLE” sign in workshop.
• Do not smoke while servicing fuel system. Keep open flames and sparks away from work area.
• Be sure to furnish the workshop with a CO
2 fire extinguisher.
CAUTION:
• Before removing fuel line parts, carry out the following procedures:
- Put drained fuel in an explosion-pr oof container and put lid on securely.
- Release fuel pressure from fuel line. Refer to EC-489, "
Fuel Pressure Check".
- Disconnect battery ground cable.
• Always replace O-ring when the fu el gauge retainer is removed.
• Do not kink or twist hose and tube when they are installed.
• Do not tighten hose and clamps excessively to avoid damaging hoses.
• After installation, run engine and check for fuel leaks at connection.
• Do not attempt to top off the fuel tank afte r the fuel pump nozzle shuts off automatically.
Continued refueling may cause fuel overflow, r esulting in fuel spray and possibly a fire.
Diagnosis ProcedureINFOID:0000000005149486
SYMPTOM: FUEL ODOR FROM EVAP CANISTER IS STRONG.
1.CHECK EVAP CANISTER
1. Remove EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor attached.
2. Weigh the EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor
attached.
The weight should be l ess than 3.2 kg (7.1 lb).
OK or NG
OK >> GO TO 2.
NG >> GO TO 3.
2.CHECK IF EVAP CANISTER SATURATED WITH WATER
PBIB1068E
Revision: April 20092010 QX56