2011 INFINITI QX56 high pressure fuel pump

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SECTION EC
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CONTENTS
ENGINE CONTROL SYSTEM
VK56VD
PRECAUTION ................ ...............................
9
PRECAUTIONS .............................................. .....9
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ......
9
Precaution for Procedure without Cowl Top Cover ......9
Precautions For Xenon Headlamp Service ...............9
On Board Diagnostic (OBD) System of Engine
and A/T ....................................................................
10
General Precautions ...............................................10
PREPARATION ...........................................14
PREPARATION .............................................. ....14
Special Service Tools .......................................... ....14
Commercial Service Tools ......................................14
SYSTEM DESCRIPTION .............................16
COMPONENT PARTS ................................... ....16
Component Parts Location .................................. ....16
Component Description ...........................................19
Accelerator Pedal Position Sensor ..........................21
Air Fuel Ratio (A/F) Sensor 1 ..................................21
ASCD Brake Switch & Stop Lamp Switch ...............21
ASCD Steering Switch ............................................21
ASCD Indicators ......................................................21
Battery Current Sensor (With Battery Tempera-
ture Sensor) ............................................................
22
Camshaft Position Sensor .......................................22
Crankshaft Position Sensor .....................................23
ECM ........................................................................23
Electric Throttle Control Actuator ............................23
Electrically-controlled cooling fan coupling .............24
Engine Coolant Temperature Sensor ......................25
Engine Oil Temperature Sensor ..............................25
EVAP Control System Pressure Sensor .................26
EVAP Canister Vent Control Valve .........................26
EVAP Canister Purge Volume Control Solenoid
Valve .................................................................... ....
26
Fuel Injector .............................................................26
Fuel Level Sensor ....................................................26
Fuel Pump Control Module ......................................27
Fuel Rail Pressure Sensor .......................................27
Fuel Tank Temperature Sensor ...............................27
Heated Oxygen Sensor 2 ........................................27
High Pressure Fuel Pump .......................................28
ICC Brake Switch & Stop Lamp Switch ...................29
ICC Steering Switch ................................................29
Ignition Coil With Power Transistor .........................29
Intake Valve Timing Control Solenoid Valve ...........29
Knock Sensor ...................................................... ....30
Low Fuel Pressure Sensor ......................................30
Low Pressure Fuel Pump ........................................30
Malfunction Indicator Lamp (MIL) ............................30
Manifold Absolute Pressure Sensor ........................31
Mass Air Flow Sensor (With Intake Air Tempera-
ture Sensor) .............................................................
31
Power Steering Pressure (PSP) Sensor ..................31
Refrigerant Pressure Sensor ............................... ....32
VVEL Actuator Motor ...............................................32
VVEL Actuator Motor Relay .....................................32
VVEL Control Module ..............................................32
VVEL Control Shaft Position Sensor .......................32
STRUCTURE AND OPERATION .....................33
Positive Crankcase Ventilation ................................33
On Board Refueling Vapor Recovery (ORVR) ........34
SYSTEM ............................................................35
ENGINE CONTROL SYSTEM ........................ ...........35
ENGINE CONTROL SYSTEM : System Diagram ....35
ENGINE CONTROL SYSTEM : System Descrip-
tion ...........................................................................
35
DIRECT INJECTION GASOLINE SYSTEM .......... ....36
DIRECT INJECTION GASOLINE SYSTEM :
System Diagram .....................................................
36
Revision: 2010 May2011 QX56

EC-8
P2A00, P2A03 A/F SENSOR 1 .......................487
DTC Logic ............................................................ ..487
Diagnosis Procedure .............................................487
ASCD BRAKE SWITCH ................................. .490
Component Function Check ................................ ..490
Diagnosis Procedure .............................................490
Component Inspection (ASCD Brake Switch) .......491
ASCD INDICATOR ..........................................492
Component Function Check ................................ ..492
Diagnosis Procedure .............................................492
ELECTRICAL LOAD SIGNAL .........................493
Description ........................................................... ..493
Component Function Check ..................................493
Diagnosis Procedure .............................................493
ELECTRICALLY-CONTROLLED COOLING
FAN COUPLING ..............................................
495
Component Function Check ................................ ..495
Diagnosis Procedure .............................................495
FUEL INJECTOR .............................................498
Component Function Check ................................ ..498
Diagnosis Procedure .............................................498
Component Inspection ...........................................499
HIGH PRESSURE FUEL PUMP ......................501
Component Function Check ................................ ..501
Diagnosis Procedure .............................................501
Component Inspection ...........................................502
ICC BRAKE SWITCH ......................................503
Component Function Check ................................ ..503
Diagnosis Procedure .............................................503
Component Inspection (ICC Brake Switch) ...........505
IGNITION SIGNAL ...........................................506
Component Function Check ................................ ..506
Diagnosis Procedure .............................................506
Component Inspection (Ignition Coil with Power
Transistor) .............................................................
509
Component Inspection (Condenser) ......................510
INFORMATION DISPLAY (ASCD) ..................511
Component Function Check ................................ ..511
Diagnosis Procedure .............................................511
LOW PRESSURE FUEL PUMP ......................512
Component Function Check ................................ ..512
Diagnosis Procedure .............................................512
Component Inspection (Low Pressure Fuel Pump)
..
513
Component Inspection (FPCM) .............................514
MALFUNCTION INDICATOR LAMP ...............515
Component Function Check ................................ ..515
Diagnosis Procedure .............................................515
ON BOARD REFUELING VAPOR RECOV-
ERY (ORVR) .....................................................
516
Component Function Check ................................ .516
Diagnosis Procedure .............................................516
Component Inspection (EVAP Vapor Cut Valve) . .518
REFRIGERANT PRESSURE SENSOR ......... ..520
Component Function Check ................................ .520
Diagnosis Procedure .............................................520
SNOW MODE SWITCH ....................................522
Description ........................................................... .522
Component Function Check .................................522
Diagnosis Procedure .............................................522
Component Inspection ..........................................523
SYMPTOM DIAGNOSIS ...........................524
ENGINE CONTROL SYSTEM SYMPTOMS .. ..524
Symptom Table .................................................... .524
NORMAL OPERATING CONDITION ...............529
Description ........................................................... .529
PERIODIC MAINTENANCE ......................530
IDLE SPEED .......................... ...........................530
Inspection ............................................................. .530
IGNITION TIMING .............................................531
Inspection ............................................................. .531
EVAP LEAK CHECK ........................................532
Inspection ............................................................. .532
POSITIVE CRANKCASE VENTILATION .........534
Inspection ............................................................. .534
REMOVAL AND INSTALLATION .............535
ECM ................................................................ ..535
Removal and Installation ...................................... .535
VVEL CONTROL MODULE .............................536
Removal and Installation ...................................... .536
FUEL PUMP CONTROL MODULE (FPCM) ....537
Removal and Installation ...................................... .537
SERVICE DATA AND SPECIFICATIONS
(SDS) ........ .................................................
538
SERVICE DATA AND SPECIFICATIONS
(SDS) .............................................................. ..
538
Idle Speed ............................................................ .538
Ignition Timing .......................................................538
Calculated Load Value ..........................................538
Mass Air Flow Sensor ...........................................538
Revision: 2010 May2011 QX56

COMPONENT PARTSEC-17
< SYSTEM DESCRIPTION > [VK56VD]
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EXHAUST COMPARTMENT
1. VVEL actuator motor (bank 2) 2. Ignition coil (with power transistor)
and spark plug (bank 2)3. Camshaft position sensor (bank 2)
4. High pressure fuel pump 5. Intake valve timing control solenoid valve (bank 2)6. Electric-viscous fan assembly
7. Engine oil temperature sensor 8. Intake valve timing control solenoid valve (bank 1)9. Camshaft position sensor (bank 1)
10. Ignition coil (with power transistor) and spark plug (bank 1) 11. VVEL actuator motor (bank 1) 12. Low fuel pressure sensor
13. Positive crankcase ventilation (PCV) valve 14. Fuel injector (bank 2) 15. Knock sensor (bank 2)
16. Knock sensor (bank 1) 17. Fuel injector (bank 1) 18. Fuel rail pressure sensor
19. Manifold absolute pressure sensor 20. VVEL control shaft position sensor (bank 1)21. Crankshaft position sensor
22. Engine coolant temperature sensor 23. VVEL control shaft position sensor (bank 2)
A. Top view of the engine (View with intake manifold is re-
moved) B. Rear view of the engine
:Engine front
JPBIA3972ZZ
Revision: 2010 May2011 QX56

EC-20
< SYSTEM DESCRIPTION >[VK56VD]
COMPONENT PARTS
High pressure fuel pump
EC-28, "High Pressure Fuel Pump"
Low pressure fuel pumpEC-30, "Low Pressure Fuel Pump"
Fuel pump control module (FPCM)EC-27, "Fuel Pump Control Module"
Fuel rail pressure sensorEC-27, "Fuel Rail Pressure Sensor"
Low fuel pressure sensorEC-30, "Low Fuel Pressure Sensor"
Fuel injectorEC-26, "Fuel Injector"
Fuel level sensorEC-26, "Fuel Level Sensor"
Fuel tank temperature sensorEC-27, "Fuel Tank Temperature Sensor"
A/F sensor 1
EC-21, "Air Fuel Ratio (A/F) Sensor 1"A/F sensor 1 heater
Heated oxygen sensor 2EC-27, "
Heated Oxygen Sensor 2"Heated oxygen sensor 2 heater
Manifold absolute pressure sensorEC-31, "
Manifold Absolute Pressure Sensor"
Knock sensorEC-30, "Knock Sensor"
Engine oil temperature sensorEC-25, "Engine Oil Temperature Sensor"
Power steering pressure sensorEC-31, "Power Steering Pressure (PSP) Sensor"
Electrically-controlled cooling fan coupling EC-24, "Electrically-controlled cooling fan coupling"
Intake valve timing control solenoid valveEC-29, "Intake Valve Timing Control Solenoid Valve"
VVEL control moduleEC-32, "VVEL Control Module"
VVEL actuator motor relayEC-32, "VVEL Actuator Motor Relay"
VVEL actuator motorEC-32, "VVEL Actuator Motor"
VVEL control shaft position sensor EC-32, "VVEL Control Shaft Position Sensor"
EVAP control system pressure sensor EC-26, "EVAP Control System Pressure Sensor"
EVAP canister vent control valveEC-26, "EVAP Canister Vent Control Valve"
EVAP canister purge volume control solenoid valveEC-26, "EVAP Canister Purge Volume Control Solenoid Valve"
Battery current sensor (with battery temperature sensor)EC-22, "Battery Current Sensor (With Battery Temperature Sen-
sor)"
Refrigerant pressure sensor
EC-32, "Refrigerant Pressure Sensor"
Stop lamp switch
EC-21, "ASCD Brake Switch & Stop Lamp Switch"ASCD brake switch
ASCD steering switchEC-21, "
ASCD Steering Switch"
Information displayEC-49, "AUTMATIC SPEED CONTROL DEVICE (ASCD) : Switch
Name and Function"
Stop lamp switch
EC-29, "ICC Brake Switch & Stop Lamp Switch"ICC brake switch
ICC steering switchEC-29, "
ICC Steering Switch"
Component Reference
Revision: 2010 May2011 QX56

COMPONENT PARTSEC-27
< SYSTEM DESCRIPTION > [VK56VD]
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The sensor detects a fuel level in the fuel tank and tr
ansmits a signal to the combination meter. The combina-
tion meter sends the fuel level sensor signal to the ECM via the CAN communication line.
It consists of two parts, one is mechanical float and the ot her is variable resistor. Fuel level sensor output volt-
age changes depending on the movement of the fuel mechanical float.
Fuel Pump Control ModuleINFOID:0000000006217674
The fuel pump control module (FPCM) controls the discharging vol-
ume of the fuel pump by transmitt ing the FPCM control signals (Low/
Mid/High) depending on driving conditions.
Fuel Rail Pressure SensorINFOID:0000000006217675
The fuel rail pressure (FRP) sensor is placed to the fuel rail and
measures fuel pressure in the fuel rail. The sensor transmits voltage
signal to the ECM. As the pressure increases, the voltage rises. The
ECM controls the fuel pressure in the fuel rail by operating high pres-
sure fuel pump. The ECM uses the signal from fuel rail pressure sen-
sor as a feedback signal.
Fuel Tank Temperature SensorINFOID:0000000006217676
The fuel tank temperature sensor is used to detect the fuel tempera-
ture inside the fuel tank. The sensor modifies a voltage signal from
the ECM. The modified signal returns to the ECM as the fuel temper-
ature input. The sensor uses a ther mistor which is sensitive to the
change in temperature. The electrical resistance of the thermistor
decreases as temperature increases.

*: These data are reference values and are measured between ECM terminals.
Heated Oxygen Sensor 2INFOID:0000000006217677
DESCRIPTION
NNBIB0006ZZ
JSBIA0291ZZ
Fuel temperature [ °C ( °F)] Voltage* (V) Resistance (k Ω)
20 (68) 3.5 2.3 - 2.7
50 (122) 2.2 0.79 - 0.90
SEF012P
Revision: 2010 May2011 QX56

EC-28
< SYSTEM DESCRIPTION >[VK56VD]
COMPONENT PARTS
The heated oxygen sensor 2, after three way catalyst (manifold),
monitors the oxygen level in the exhaust gas on each bank.
Even if switching characteristics of
the air fuel ratio (A/F) sensor 1
are shifted, the air fuel ratio is c ontrolled to stoichiometric, by the sig-
nal from the heated oxygen sensor 2.
This sensor is made of ceramic zirconia. The zirconia generates volt-
age from approximately 1 V in richer conditions to 0 V in leaner con-
ditions.
Under normal conditions the heated ox ygen sensor 2 is not used for
engine control operation.
HEATED OXYGEN SENSOR 2 HEATER
Heated oxygen sensor 2 heater is integrated in the sensor.
The ECM performs ON/OFF control of the heated oxy gen sensor 2 heater corresponding to the engine speed,
amount of intake air and engine coolant temperature.
High Pressure Fuel PumpINFOID:0000000006217678
The high pressure fuel pump is installed at the front of the engine bank 2 side and activated by the camshaft.
ECM controls the high pressure fuel pump control sol enoid valve built into the high pressure fuel pump and
adjusts the amount of discharge by changing the suction timing of the low pressure fuel.
Operating Description
SEF327R
Engine speed Heated oxygen sensor 2 heater
Above 3,600 rpm OFF
Below 3,600 rpm after the following conditions are met.
 Engine: After warming up
 Keeping the engine speed between 3,500 and 4,000 rpm for 1 minute and at idle for 1 minute under no load ON
JSBIA0285GB
Revision: 2010 May2011 QX56

SYSTEMEC-39
< SYSTEM DESCRIPTION > [VK56VD]
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Fuel is injected into each cylinder during each engine cycle accord-
ing to the ignition order.
STRATIFIED-CHARGE START CONTROL
The use of the stratified-charge combustion met
hod enables emissions-reduction when starting the engine
with engine coolant temperature between 5 °C (41 °F) and 40 °C (104 °F).
FUEL SHUT-OFF
Fuel to each cylinder is shut-off during deceleration, operation of the engine at excessively high speed or oper-
ation of the vehicle at excessively high speed.
FUEL PRESSURE CONTROL
FUEL PRESSURE CONTROL : System DiagramINFOID:0000000006217701
FUEL PRESSURE CONTROL : System DescriptionINFOID:0000000006217702
INPUT/OUTPUT SIGNAL CHART
JSBIA0407GB
JSBIA0315GB
Sensor Input signal to ECM ECM function Actuator
Crankshaft position sensor Engine speed
Fuel injection
& mixture ratio
controlHigh pressure fuel pump
Camshaft position sensor Camshaft position
Fuel rail pressure sensor Fuel rail pressure
Low fuel pressure sensor Low fuel pressure
Engine coolant temperature sensor Engine coolant temperature
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Battery Battery voltage
Revision: 2010 May2011 QX56

EC-40
< SYSTEM DESCRIPTION >[VK56VD]
SYSTEM
SYSTEM DESCRIPTION
Low fuel pressure control
 The low fuel pressure pump is controlled by the f
uel pump control module (FPCM) and pumps fuel according
to a driving condition. The pumped fuel passes through t he fuel filter and is sent to the high pressure fuel
pump. FPCM controls the low pressure fuel pump, ac cording to a signal from ECM as shown in the table
below.
 Low fuel pressure is adjusted by the fuel pressure regulator.
High fuel pressure control
 The high pressure fuel pump raises the pressure of the fuel sent from the low pressure fuel pump. Actuated
by the camshaft, the high pressure fuel pump activates the high pressure fuel pump solenoid based on a sig-
nal received from ECM, and adjusts the amount of di scharge by changing the timing of closing the inlet
check valve to control fuel rail pressure.
COOLING FAN CONTROL
JSBIA0235GB
Conditions Amount of fuel flow Supplied voltage
After a laps of 1 second after ignition ON OFF 0 V
 For 1 second after turning ignition switch ON
 Engine is running under low load and low speed conditions Low Approximately 8.5 V
 Engine cranking
 Engine coolant temperature is below 10 °C (50 °F)
 Engine is running under high load and high speed conditions High
Battery voltage
(11 – 14 V)
Except the above Mid Approximately 10 V
Revision: 2010 May2011 QX56