2011 INFINITI QX56 Fuel

EC-512
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
LOW PRESSURE FUEL PUMP
LOW PRESSURE FUEL PUMP
Component Function CheckINFOID:0000000006218017
1.CHECK FUEL PUMP FUNCTION
1. Turn ignition switch ON.
2. Pinch fuel feed hose with two fingers. NOTE:
Fuel pressure pulsation should be felt on the fuel feed hose for 1 second after ignition switch is turned ON.
Is the inspection result normal?
YES >> INSPECTION END
NO >> EC-512, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000006218018
1.CHECK FPCM POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect FPCM harness connector.
3. Turn ignition switch ON.
4. Check the voltage between FPCM 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 FPCM GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Check the continuity between FPCM harness connector and ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair open circuit or short to power in harness or connectors.
3.CHECK FPCM INPUT AND OUTPUT CIRCUIT
1. Disconnect ECM harness connector.
2. Check the continuity between FPCM harness connector and ECM harness connector.
3. Also check harness for short to ground and to power.
Is the inspection result normal?
+ −Voltag e
FPCM
Connector Terminal B41 10 Ground Battery voltage
+ −Continuity
FPCM
Connector Terminal B41 5 Ground Existed
+ −
Continuity
FPCM ECM
Connector Terminal Connector Terminal
B41 8
E80 125
Existed
9142
Revision: 2010 May2011 QX56

LOW PRESSURE FUEL PUMPEC-513
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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YES >> GO TO 4.
NO >> Repair or replace error-detected parts.
4.CHECK FUEL PUMP CONTROL CIRCUIT
1. Disconnect fuel level sensor unit and fuel pump harness connector.
2. Check the continuity between FPCM harness connecto r and fuel level sensor unit and fuel pump harness
connector.
3. Also check harness for short to ground and to power.
Is the inspection result normal?
YES >> GO TO 5.
NO >> Repair or replace error-detected parts.
5.CHECK LOW PRESSURE FUEL PUMP
Refer to EC-513, "
Component Inspection (Low Pressure Fuel Pump)".
Is the inspection result normal?
YES >> GO TO 6.
NO >> Replace fuel level sensor unit and fuel pump. Refer to FL-5, "
Removal and Installation".
6.CHECK FPCM
Refer to EC-514, "
Component Inspection (FPCM)".
Is the inspection result normal?
YES >> Check intermittent incident. Refer to GI-40, "Intermittent Incident".
NO >> Replace FPCM. Refer to EC-537, "
Removal and Installation".
Component Inspection (Low Pressure Fuel Pump)INFOID:0000000006218019
1.CHECK FUEL PRESSURE REGULATOR
1. Turn ignition switch OFF.
2. Check low fuel pressure. Refer to EC-153, "
Work Procedure".
Is inspection result normal?
YES >> INSPECTION END
NO >> GO TO 2.
2.CHECK LOW PRESSURE FUEL PUMP
1. Turn ignition switch OFF.
2. Disconnect fuel level sensor unit and fuel pump.
3. Check resistance between fuel level sens or unit and fuel pump terminals as follows.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace fuel level sensor unit and fuel pump. Refer to FL-5, "
Removal and Installation".
+−
Continuity
FPCM Fuel level sensor unit and fuel pump
Connector Terminal Connector Terminal
B41 6
C5 3
Existed
71
+ −
Condition Resistance
Fuel level sensor unit and fuel
pump
Te r m i n a l s
1 3 Temperature: 25 °C (77 °F) 0.2 - 5.0 Ω
Revision: 2010 May2011 QX56

EC-514
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
LOW PRESSURE FUEL PUMP
Component Inspection (FPCM)
INFOID:0000000006218020
1.CHECK FUEL PUMP CONTROL MODULE (FPCM)
1. Check the voltage between FPCM terminals under the following conditions.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace FPCM. Refer to EC-537, "
Removal and Installation".
FPCM
Condition Voltage
+ −
Te r m i n a l Te r m i n a l
76 For 1 second after
turning ignition
switch ON Approx. 8.5 V
More than 1 seco nd after turning
ignition switch ON Approx. 0 V
Idle speed Approx. 8.5 V
Revision: 2010 May2011 QX56

EC-516
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
ON BOARD REFUELING VAPOR RECOVERY (ORVR)
ON BOARD REFUELING VA
POR RECOVERY (ORVR)
Component Function CheckINFOID:0000000006256490
1.CHECK ORVR FUNCTION
Check whether the following symptoms are present.
 Fuel odor from EVAP canister is strong.
 Cannot refuel/Fuel odor from the fuel filler opening is strong while refueling.
Are any symptoms present?
YES >> Proceed to EC-516, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006256491
1.INSPECTION START
Check whether the following symptoms are present.
A: Fuel odor from EVAP canister is strong.
B: Cannot refuel/Fuel odor from the fuel filler opening is strong while refueling.
Which symptom is present?
A>>GO TO 2.
B>>GO TO 7.
2.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 2.5 kg (5.5 lb).
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 4.
3.CHECK IF EVAP CANISTER IS SATURATED WITH WATER
Check if water will drain from EVAP canister (1).
 EVAP canister vent control valve (2)
Does water drain from the EVAP canister?
YES >> GO TO 4.
NO >> GO TO 6.
4.REPLACE EVAP CANISTER
Replace EVAP canister with a new one.
>> GO TO 5.
5.DETECT MALFUNCTIONING PART
Check the EVAP hose between EVAP canister and vehicle frame for clogging or poor connection.
>> Repair or replace EVAP hose.
6.CHECK REFUELING EVAP VAPOR CUT VALVE
Refer to EC-518, "
Component Inspection (EVAP Vapor Cut Valve)".
JSBIA0692ZZ
Revision: 2010 May2011 QX56

ON BOARD REFUELING VAPOR RECOVERY (ORVR)EC-517
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace refueling EVAP vapor cut valve with fuel tank.
7.CHECK EVAP CANISTER
1. Remove EVAP canister with EVAP canister vent c ontrol 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 2.5 kg (5.5 lb).
Is the inspection result normal?
YES >> GO TO 8.
NO >> GO TO 9.
8.CHECK IF EVAP CANISTER IS SATURATED WITH WATER
Check if water will drain from EVAP canister (1).
 EVAP canister vent control valve (2)
Does water drain from the EVAP canister?
YES >> GO TO 9.
NO >> GO TO 11.
9.REPLACE EVAP CANISTER
Replace EVAP canister with a new one.
>> GO TO 10.
10.DETECT MALFUNCTIONING PART
Check the EVAP hose between EVAP canister and vehicle frame for clogging or poor connection.
>> Repair or replace EVAP hose.
11 .CHECK VENT HOSES AND VENT TUBES
Check hoses and tubes between EVAP c anister and refueling control valve for clogging, kinks, looseness and
improper connection.
Is the inspection result normal?
YES >> GO TO 12.
NO >> Repair or replace hoses and tubes.
12.CHECK FILLER NECK TUBE
Check recirculation line for clogging, dents and cracks.
Is the inspection result normal?
YES >> GO TO 13.
NO >> Replace filler neck tube.
13.CHECK REFUELING EVAP VAPOR CUT VALVE
Refer to EC-518, "
Component Inspection (EVAP Vapor Cut Valve)".
Is the inspection result normal?
YES >> GO TO 14.
NO >> Replace refueling EVAP vapor cut valve with fuel tank.
14.CHECK FUEL FILLER TUBE
Check filler neck tube and hose connected to the fuel tank for clogging, dents and cracks.
JSBIA0692ZZ
Revision: 2010 May2011 QX56

EC-518
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
ON BOARD REFUELING VAPOR RECOVERY (ORVR)
Is the inspection result normal?
YES >> GO TO 15.
NO >> Replace fuel filler tube.
15.CHECK ONE-WAY FUEL VALVE-I
Check one-way fuel valve for clogging.
Is the inspection result normal?
YES >> GO TO 16.
NO >> Repair or replace one-way fuel valve with fuel tank.
16.CHECK ONE-WAY FUEL VALVE-II
1. Check that fuel is drained from the tank.
2. Remove fuel filler tube and hose.
3. Check one-way fuel valve for operation as per the following.
When a stick is inserted, the valve should open, when removing
stick it should close.
Do not drop any material into the tank.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace fuel filler tube or replace one-way fuel valve with fuel tank.
Component Inspection (EVAP Vapor Cut Valve)INFOID:0000000006256492
1.CHECK REFUELING EVAP VAPOR CUT VALVE
1. Turn ignition switch OFF.
2. Remove fuel tank. Refer to FL-8, "
Removal and Installation".
3. Drain fuel from the tank as per the following:
- Remove fuel gauge retainer.
- Drain fuel from the tank using a handy pump into a fuel container.
4. Check refueling EVAP vapor cut valve for being stuck to close as per the following.
Blow air into the refueling EVAP vapor cut valv e (from the end of EVAP/ORVR line hose), and check that
the air flows freely into the tank.
5. Check refueling EVAP vapor cut valve for being stuck to open as per the following.
- Connect vacuum pump to hose end.
- Remove fuel gauge retainer with fuel gauge unit. Always replace O-ri ng with new one.
- Turn fuel tank upside down.
SEF665U
Revision: 2010 May2011 QX56

ON BOARD REFUELING VAPOR RECOVERY (ORVR)EC-519
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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- Apply vacuum pressure to hose end [
−13.3 kPa ( −0.136 kg/cm3, −1.93 psi)] with fuel gauge retainer
remaining open and check that the pressure is applicable.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace refueling EVAP vapor cut valve with fuel tank.
JSBIA0605GB
Revision: 2010 May2011 QX56

EC-524
< SYMPTOM DIAGNOSIS >[VK56VD]
ENGINE CONTROL SYSTEM SYMPTOMS
SYMPTOM DIAGNOSIS
ENGINE CONTROL SYSTEM SYMPTOMS
Symptom TableINFOID:0000000006218028
SYSTEM — BASIC ENGINE CONTROL SYSTEM
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
Fuel Low pressure fuel pump circuit 11232 22 3 2 EC-512
Low fuel pressure sensor circuit 4 4EC-483
Fuel pressure regulator system 334444444 4EC-198
Fuel injector circuit 11232 22 2EC-498
Evaporative emission system 334444444 4EC-532
FRP sensor circuit 11222 22 2EC-276EC-279
High pressure fuel pump circuit 4 3
EC-501
Air Positive crankcase ventilation sys-
tem 334444444 41
EC-534
Incorrect idle speed adjustment 1 1 1 1 1 EC-139
Electric throttle control actuator 112332222 2 2EC-460EC-466
IgnitionIncorrect ignition timing adjustment33111 11 1
EC-139
Ignition circuit 11222 22 2EC-506
Main power supply and ground circuit 22333 33 23 EC-168
Revision: 2010 May2011 QX56