2011 INFINITI QX56 Fuel

EC-10
< PRECAUTION >[VK56VD]
PRECAUTIONS
CAUTION:
Comply with the following cautions to
prevent any error and malfunction.
 Install the xenon bulb securely. (Ins ufficient bulb socket installation may melt the bulb, the connec-
tor, the housing, etc. by high-v oltage leakage or corona discharge.)
 Never perform HID circuit in spection with a tester.
 Never touch the xenon bulb glass with ha nds. Never put oil and grease on it.
 Dispose of the used xenon bulb after packing it in thick vinyl without breaking it.
 Never wipe out dirt and cont amination with organic solven t (thinner, gasoline, etc.).
On Board Diagnostic (OBD) System of Engine and A/TINFOID:0000000006217652
The ECM has an on board diagnostic system. It will illuminate the malfunction indicator lamp (MIL) to warn the
driver of a malfunction causing emission deterioration.
CAUTION:
 Always turn the ignition switch OFF and disconnect the negative battery cable before any repair or
inspection work. The open/short circuit of related sw itches, sensors, solenoid valves, etc. will cause
the MIL to illuminate.
 Always connect and lock the conn ectors securely after work. A loose (unlocked) connector will
cause the MIL to illuminate due to the open circuit. (Be sure the connector is free from water, grease,
dirt, bent terminals, etc.)
 Certain systems and components, especially those related to OBD, may use a new style slide-lock-
ing type harness connector. For descripti on and how to disconnect, refer to EC-51, "
Diagnosis
Description".
 Always route and secure the harnesses properly afte r work. The interference of the harness with a
bracket, etc. may cause the MIL to illu minate due to the short circuit.
 Always connect rubber tubes properly after work. A misconnected or disconnected rubber tube may
cause the MIL to illuminate due to the malfunction of the EVAP system or fuel injection system, etc.
 Always erase the unnecessary malfunction information (repairs completed) from the ECM and TCM
(Transmission control module) before re turning the vehicle to the customer.
General PrecautionsINFOID:0000000006217653
Always use a 12 volt battery as power source.
 Never attempt to disconnect battery cables while engine is
running.
 Before connecting or disconnecting the ECM harness con-
nector, turn ignition switch OFF and disconnect negative bat-
tery cable. Failure to do so may damage the ECM because
battery voltage is applied to ECM even if ignition switch is
turned OFF.
 Before removing parts, turn ig nition switch OFF and then dis-
connect battery ground cable.
 Never disassemble ECM.
 If a battery cable is disconnected, the memory will return to
the ECM value.
The ECM will now start to self-control at its initial value. Thus,
engine operation can vary slight ly in this case. However, this
is not an indication of a ma lfunction. Never replace parts
because of a slight variation.
 If the battery is disconnected, the following emission-related
diagnostic information will be lost within 24 hours.
- Diagnostic trouble codes
- 1st trip diagnostic trouble codes
- Freeze frame data
- 1st trip freeze frame data
- System readiness test (SRT) codes
- Test values
SEF289H
JMBIA0057ZZ
Revision: 2010 May2011 QX56

EC-12
< PRECAUTION >[VK56VD]
PRECAUTIONS

When measuring ECM signals with a circuit tester, never allow
the two tester probes to contact.
Accidental contact of probes will cause a short circuit and
damage the ECM power transistor.
 B1 indicates bank 1, B2 indicat es bank 2 as shown in the fig-
ure.
 Never operate fuel pump when there is no fuel in lines.
 Tighten fuel hose clamps to the specified torque.
 Never depress accelerator pedal when starting.
 Immediately after starting, never rev up engine unnecessarily.
 Never rev up engine just prior to shutdown.
SEF348N
PBIB1144E
SEF709Y
Revision: 2010 May2011 QX56

EC-14
< PREPARATION >[VK56VD]
PREPARATION
PREPARATION
PREPARATION
Special Service ToolsINFOID:0000000006217654
Commercial Service ToolsINFOID:0000000006217655
Tool number
(Kent-Moore No.)
Tool nameDescription
KV10118400
(—)
Fuel tube adapter Measures fuel pressure
PBIB3043E
Tool name
(Kent-Moore No.)
Description
Leak detector
i.e.: (J-41416) Locates the EVAP leak
EVAP service port adapter
i.e.: (J-41413-OBD) Applys positive pressure through EVAP service
port
Fuel filler cap adapter
i.e.: (MLR-8382) Checks fuel tank vacuum relief valve opening
pressure
Socket wrench Removes and installs engine coolant temperature sensor
S-NT703
S-NT704
S-NT815
S-NT705
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

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. 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

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-21
< SYSTEM DESCRIPTION > [VK56VD]
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Accelerator Pedal
Position SensorINFOID:0000000006217658
The accelerator pedal position (APP) sensor is installed on the
accelerator pedal assembly. The sensor detects the accelerator
position and sends a signal to the ECM.
Accelerator pedal position sensor has two sensors. These sensors
are a kind of potentiometer which transform the accelerator pedal
position into output voltage, and emit the voltage signals to the ECM.
The ECM judges the current opening angle of the accelerator pedal
from these signals and controls the throttle control motor based on
these signals.
Idle position of the accelerator pedal is determined by the ECM
receiving the signal from the accelerator pedal position sensor. The
ECM uses this signal for engine operations such as fuel cut.
Air Fuel Ratio (A/F) Sensor 1INFOID:0000000006217659
DESCRIPTION
The sensor element of the A/F sensor 1 is composed an electrode 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 sens or 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 hydrocarbon 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 approxi-
mately 760 °C (1,400 °F).
A/F SENSOR 1 HEATER
A/F sensor 1 heater is integrated in the sensor.
The ECM performs ON/OFF duty control of the A/F sensor 1 heater corresponding to the engine operating
condition to keep the temperature of A/F s ensor 1 element within the specified range.
ASCD Brake Switch & Stop Lamp Switch INFOID:0000000006217660
Stop lamp switch and ASCD brake switch are installed to brake pedal bracket.
When the brake pedal is depressed, ASCD brake switch is turned OFF and stop lamp switch is turned ON.
ECM detects the state of the brake pedal by those two types of input (ON/OFF signal).
ASCD Steering SwitchINFOID:0000000006217661
ASCD steering switch has variant values of electrical resistance for each button. ECM reads voltage variation
of switch, and determines which button is operated.
ASCD IndicatorsINFOID:0000000006217662
ASCD operation status is indicated by CRUISE indicator in combination meter.
ECM transmits the ASCD status signal to the combi nation meter via CAN communication according to ASCD
operation.
PBIB1741E
JSBIA0527GB
Revision: 2010 May2011 QX56

EC-22
< SYSTEM DESCRIPTION >[VK56VD]
COMPONENT PARTS
Battery Current Sensor (With Battery Temperature Sensor)
INFOID:0000000006217663
OUTLINE
The power generation voltage variable control enables fuel con-
sumption to be decreased by reducing the engine load which is
caused by the power generation of the generator.
Based on sensor signals, ECM judges whether or not the power
generation voltage variable control is performed. When performing
the power generation voltage variable control, ECM calculates the
target power generation voltage based on the sensor signal. And
ECM sends the calculated value as the power generation command
value to IPDM E/R. For the details of the power generation voltage
variable control, refer to CHG-7, "
POWER GENERATION VOLTAGE
VARIABLE CONTROL SYSTEM : System Description".
CAUTION:
Never connect the electrical component or the groun d wire directly to the battery terminal. The con-
nection causes the malfunction of th e power generation voltage variable control, and then the battery
discharge may occur.
BATTERY CURRENT SENSOR
The battery current sensor is installed to the battery cable at the negative terminal. The sensor measures the
charging/discharging current of the battery.
BATTERY TEMPERATURE SENSOR
Battery temperature sensor is int egrated in battery current sensor.
The sensor measures ambient temperature around the battery.
The electrical resistance of the t hermistor decreases as temperature
increases.

*: These data are reference values and are measured between ECM terminals.
Camshaft Position SensorINFOID:0000000006217664
The camshaft position (CMP) sensor senses the protrusion of the
signal plate installed to the camshaft (INT) front end to identify a par-
ticular cylinder. The camshaft position sensor senses the piston posi-
tion.
The sensor consists of a permanent magnet and Hall IC.
When engine is running, the high and low parts of the teeth cause
the gap with the sensor to change.
The changing gap causes the magnetic field near the sensor to
change.
Due to the changing magnetic field, the voltage from the sensor
changes.
When the crankshaft position sens or system becomes inoperative,
the camshaft position sensor provides various controls of engine parts instead, utilizing timing of cylinder iden-
tification signals.
JPBIA3262ZZ
Temperature [ °C ( °F)] Voltage* (V) Resistance (k Ω)
25 (77) 3.333 1.9 - 2.1
90 (194) 0.969 0.222 - 0.258
SEF012P
JMBIA0064ZZ
Revision: 2010 May2011 QX56