
EC-1
ENGINE
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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
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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 INFINITI QX56 2011 Factory Service Manual
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](/manual-img/42/57033/w960_57033-2040.png)
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
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COMPONENT PARTSEC-19
< SYSTEM DESCRIPTION > [VK56VD]
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Component DescriptionINFOID:0000000006217657
1. ASCD steering switch
ICC steering switch 2. Snow mode switch 3. Fu INFINITI QX56 2011 Factory Service Manual
COMPONENT PARTSEC-19
< SYSTEM DESCRIPTION > [VK56VD]
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Component DescriptionINFOID:0000000006217657
1. ASCD steering switch
ICC steering switch 2. Snow mode switch 3. Fu](/manual-img/42/57033/w960_57033-2042.png)
COMPONENT PARTSEC-19
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Component DescriptionINFOID:0000000006217657
1. ASCD steering switch
ICC steering switch 2. Snow mode switch 3. Fuel level sensor unit and fuel pump
assembly (with fuel tank temperature
sensor)
4. Fuel pump control module (FPCM) 5. EVAP canister vent control valve 6. EVAP canister
7. EVAP control system pressure sen- sor 8. Stop lamp switch 9. ASCD brake switch
ICC brake switch
10. Accelerator pedal position sensor
JSBIA0606ZZ
Component Reference
ECM EC-23, "
ECM"
Malfunction indicator lamp (MIL)EC-30, "Malfunction Indicator Lamp (MIL)"
Ignition coil with power transistorEC-29, "Ignition Coil With Power Transistor"
Accelerator pedal position sensorEC-21, "Accelerator Pedal Position Sensor"
Mass air flow sensor
EC-31, "Mass Air Flow Sensor (With Intake Air Temperature Sen-
sor)"Intake air temperature sensor
Electric throttle control actuator
EC-23, "
Electric Throttle Control Actuator"Throttle control motor relay
Throttle control motor
Throttle position sensor
Crankshaft position sensorEC-23, "
Crankshaft Position Sensor"
Camshaft position sensorEC-22, "Camshaft Position Sensor"
Engine coolant temperature sensorEC-25, "Engine Coolant Temperature Sensor"
Revision: 2010 May2011 QX56
![INFINITI QX56 2011 Factory Service Manual
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-2 INFINITI QX56 2011 Factory Service Manual
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-2](/manual-img/42/57033/w960_57033-2043.png)
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
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EC-70
< SYSTEM DESCRIPTION >[VK56VD]
DIAGNOSIS SYSTEM (ECM)
*: The item is indicated, but not used.
NOTE:
Any monitored item that does not match the vehicle being diagnosed is deleted from the displa INFINITI QX56 2011 Factory Service Manual
EC-70
< SYSTEM DESCRIPTION >[VK56VD]
DIAGNOSIS SYSTEM (ECM)
*: The item is indicated, but not used.
NOTE:
Any monitored item that does not match the vehicle being diagnosed is deleted from the displa](/manual-img/42/57033/w960_57033-2093.png)
EC-70
< SYSTEM DESCRIPTION >[VK56VD]
DIAGNOSIS SYSTEM (ECM)
*: The item is indicated, but not used.
NOTE:
Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.
ACTIVE TEST MODE
Test Item
ECM TEMP 1
°C or °F Displays a temperature calculated from a signal of
ECM temperature sensor 1.
ECM TEMP 2 °C or °F Displays a temperature calculated from a signal of
ECM temperature sensor 2.
FUEL PUMP DUTY % The control condition of the fuel pump control mod-
ule (FPCM) (determined by ECM according to the
input signals) is indicated.
Monitored item Unit Description Remarks
TEST ITEM CONDITION JUDGMENT CHECK ITEM (REMEDY)
VENT CON-
TROL/V Ignition switch: ON (Engine
stopped)
Turn solenoid valve ON and OFF with the CONSULT-III and listen
to operating sound. Solenoid valve makes an operating
sound.
Harness and connectors
Solenoid valve
ENG COOLANT
TEMP Engine: Return to the original
non-standard condition
Change the engine coolant tem- perature using CONSULT-III. If malfunctioning symptom disap-
pears, see CHECK ITEM. Harness and connectors
Engine coolant temperature sen-
sor
Fuel injector
FUEL INJEC-
TION Engine: Return to the original
non-standard condition
Change the amount of fuel injec- tion using CONSULT-III. If malfunctioning symptom disap-
pears, see CHECK ITEM.
Harness and connectors
Fuel injector
Air fuel ratio (A/F) sensor 1
FUEL/T TEMP
SEN Change the fuel tank temperature using CONSULT-III.
PURG VOL
CONT/V Engine: After warming up, run en-
gine at 1,500 rpm.
Change the EVAP canister purge
volume control solenoid valve
opening percent using CON-
SULT-III. Engine speed changes according to
the opening percent.
Harness and connectors
Solenoid valve
FAN DUTY CON-
TROL* Ignition switch: ON
Change duty ratio using CON-
SULT-III. Cooling fan speed changes. Harness and connectors
Cooling fan motor
Cooling fan relay
Cooling fan control module
IPDM E/R
ALTERNATOR
DUTY Engine: Idle
Change duty ratio using CON-
SULT-III. Battery voltage changes. Harness and connectors
IPDM E/R
Alternator
POWER BAL-
ANCE Engine: After warming up, idle the
engine.
A/C switch OFF
Selector lever: P or N
Cut off each injector signal one at a time using CONSULT-III. Engine runs rough or stops.
Harness and connectors
Compression
Fuel injector
Power transistor
Spark plug
Ignition coil
IGNITION TIM-
ING Engine: Return to the original
non-standard condition
Timing light: Set
Retard the ignition timing using
CONSULT-III. If malfunctioning symptom disap-
pears, see CHECK ITEM.
Perform Idle Air Volume Learning.
Revision: 2010 May2011 QX56
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EC-94
< ECU DIAGNOSIS INFORMATION >[VK56VD]
ECM
DTC No. Detected items Engine operating condition in fail-safe mode
U0113
U1003
U1024 Can communication circuit VVEL actuator
motor relay is turned of INFINITI QX56 2011 Factory Service Manual
EC-94
< ECU DIAGNOSIS INFORMATION >[VK56VD]
ECM
DTC No. Detected items Engine operating condition in fail-safe mode
U0113
U1003
U1024 Can communication circuit VVEL actuator
motor relay is turned of](/manual-img/42/57033/w960_57033-2117.png)
EC-94
< ECU DIAGNOSIS INFORMATION >[VK56VD]
ECM
DTC No. Detected items Engine operating condition in fail-safe mode
U0113
U1003
U1024 Can communication circuit VVEL actuator
motor relay is turned off, and VVEL value is become at a minimum angle.
Engine speed will not rise more than 3,500 rpm due to the fuel cut.
P0011
P0021 Intake valve timing control The signal is not energized to the intake valve timing control solenoid valve and the valve
control does not function.
P0087 FRP control system Engine torque is limited.
VVEL value is maintained at a fixed angle.
P0088 Engine speed is limited.
P008A Low fuel pressure control
system Engine torque is limited.
P0090 FRP control system Engine torque is limited.
VVEL value is maintained at a fixed angle.
P0102
P0103 Mass air flow sensor circuit Engine speed will not rise more than 2,400 rpm due to the fuel cut.
P0117
P0118 Engine coolant tempera-
ture sensor circuit
Engine coolant temperature will be determined by ECM based on the following condition.
CONSULT-III displays the engine coolant temperature decided by ECM.
Condition Engine coolant temperature decided
(CONSULT-III display)
Just as ignition switch is turned ON
or START 40
°C (104 °F)
Approx. 4 minutes or more after
engine starting 80
°C (176 °F)
Except as shown above 40 - 80 °C (104 - 176 °F)
(Depends on the time)
When the fail-safe system for engine coolant temperature sensor is activated, the cooling
fan operates while engine is running.
P0122
P0123
P0222
P0223
P2135 Throttle position sensor The ECM controls the electric throttle control actuator in regulating the throttle opening in
order for the idle position to be within +10 degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the normal
condition.
Therefore, the acceleration will be poor.
P0190 FRP sensor Engine speed is limited.
High pressure fuel pump is activated at maximum discharge pressure.
P0201
P0202
P0203
P0204
P0205
P0206
P0207
P0208 Injector Engine torque is limited.
Fuel injection shut-off of malfunction cylinder.
Mixture ratio feedback control does not function.
Idle engine speed is increased.
P0500 Vehicle speed sensor The cooling fan operates (Highest) while engine is running.
P0524 Engine oil pressure The signal is not energized to the intake valve timing control solenoid valve and the valve
control does not function.
Engine speed will not rise more than 2,400 rpm due to the fuel cut.
P0605 ECM (When ECM calculation function is malfunctioning:)
ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.
ECM deactivates ASCD operation.
P0607 ECM VVEL actuator motor relay is
turned off, and VVEL value is become at a minimum angle.
Engine speed will not rise more than 3,500 rpm due to the fuel cut.
Revision: 2010 May2011 QX56
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ECM
EC-97
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Priority Detected items (DTC)
1 U0101 CAN communication line U0113 U1003 CAN communication line
U1001 CAN commun INFINITI QX56 2011 Factory Service Manual
ECM
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Priority Detected items (DTC)
1 U0101 CAN communication line U0113 U1003 CAN communication line
U1001 CAN commun](/manual-img/42/57033/w960_57033-2120.png)
ECM
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Priority Detected items (DTC)
1 U0101 CAN communication line U0113 U1003 CAN communication line
U1001 CAN communication line
U1024 VVEL CAN communication line
P006A P0101 P0102 P0103 Mass air flow sensor
P010A Manifold absolute pressure sensor
P0112 P0113 P0127 Intake air temperature sensor
P0116 P0117 P0118 P0125 Engine coolant temperature sensor
P0122 P0123 P0222 P0223 P1225 P1226 P2135 Throttle position sensor
P0128 Thermostat function
P0181 P0182 P0183 Fuel tank temperature sensor
P0196 P0197 P0198 Engine oil temperature sensor
P0327 P0328 P0332 P0333 Knock sensor
P0335 Crankshaft position sensor
P0340 P0345 Camshaft position sensor
P0460 P0461 P0462 P0463 Fuel level sensor
P0500 Vehicle speed sensor
P0527 Cooling fan speed sensor
P0605 P0607 P0611 P062B ECM
P0643 Sensor power supply
P0700 TCM
P0705 P0850 Transmission range switch
P1089 P1092 P1608 VVEL control shaft position sensor
P1197 Out of gas*
P1220 Fuel pump control module (FPCM)
P1421 P1423 P1424 Cold start control
P1550 P1551 P1552 P1553 P1554 Battery current sensor
P1556 P1557 Battery temperature sensor
P1606 P1607 VVEL control module
P1610 - P1615 NATS
P2122 P2123 P2127 P2128 P2138 Accelerator pedal position sensor
P2539 P2541 P2542 Low fuel pressure sensor
Revision: 2010 May2011 QX56