2014 NISSAN TEANA fuel

EC-26
< SYSTEM DESCRIPTION >[QR25DE]
COMPONENT PARTS
THROTTLE CONTROL MOTOR RELAY
Power supply for the throttle control motor is provided to
the ECM via throttle control motor relay. The throttle
control motor relay is ON/OFF controlled by the ECM. When the ignition switch is turned ON, the ECM sends
an ON signal to throttle control motor relay and battery voltage is provided to the ECM. When the ignition
switch is turned OFF, the ECM sends an OFF signal to throttle control motor relay and battery voltage is not
provided to the ECM.
THROTTLE CONTROL MOTOR
The throttle control motor is operated by the ECM and it opens and closes the throttle valve.
The current opening angle of the throttle valve is detected by the throttle position sensor and it provides feed-
back to the ECM to control the throttle control mo tor to make the throttle valve opening angle properly in
response to driving condition.
THROTTLE POSITION SENSOR
The throttle position sensor responds to the throttle valve movement.
The throttle position sensor has two sensors. These sensors are a
kind of potentiometers which transform the throttle valve position into
output voltage, and emit the voltage signal to the ECM. In addition,
these sensors detect the opening and closing speed of the throttle
valve and feed the voltage signals to the ECM. The ECM judges the
current opening angle of the throttle valve from these signals and the
ECM controls the throttle control motor to make the throttle valve
opening angle properly in response to driving condition.
Ignition Coil With Power TransistorINFOID:0000000009462057
The ignition signal from the ECM is sent to and amplified 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.
Fuel InjectorINFOID:0000000009462058
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.
Fuel Level Sensor Unit and Fuel PumpINFOID:0000000009462059
FUEL PUMP
PBIB0145E
JPBIA4613ZZ
JPBIA5845ZZ
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COMPONENT PARTSEC-27
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The ECM activates the fuel pump for 1 second after the ignition
switch is turned ON to improve engine start ability. 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 igni-
tion switch is ON, the engine stalls. The ECM stops pump operation
and prevents battery discharging, thereby improving safety. The
ECM does not directly drive the fuel pump. It sends the control signal
to the fuel pump control module, which in turn controls the fuel
pump.
FUEL LEVEL SENSOR
The fuel level sensor is mounted in the fuel level sensor unit.
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 Tank Temperature SensorINFOID:0000000009462060
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.
Mass Air Flow Sensor (With Intake Air Temperature Sensor)INFOID:0000000009462061
MASS AIR FLOW SENSOR
JPBIA5842ZZ
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 .
SEF012P
Fluid temperature
[° C ( °F)] Voltage* (V) Resistance (k
Ω)
20 (68) 3.5 2.3 - 2.7
50 (122) 2.2 0.79 - 0.90
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EC-32
< SYSTEM DESCRIPTION >[QR25DE]
COMPONENT PARTS
Air Fuel Ratio (A/F) Sensor 1
INFOID:0000000009462072
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 sensor outputs a cl ear, continuous signal throughout a wide range.
The exhaust gas components diffuse through the diffusi on layer at the sensor cell. An electrode layer is
applied voltage, and this current relati ve 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 additi on, 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.
Heated Oxygen Sensor 2INFOID:0000000009462073
The heated oxygen sensor 2, after three way catalyst (manifold),
monitors the oxygen level in the exhaust gas.
Even if switching characteristics of the air fuel ratio (A/F) sensor 1
are shifted, the air fuel ratio is controlled 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.
JPBIA4038GB
JPBIA5446GB
SEF327R
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EC-34
< SYSTEM DESCRIPTION >[QR25DE]
COMPONENT PARTS

*: These data are reference values and are measured between ECM terminals.
Cooling FanINFOID:0000000009462077
The ECM controls the cooling fan corresponding to the
vehicle speed, engine coolant temperature, refrigerant
pressure, and air conditioner ON signal. The control system has 4-step control [HIGH/MIDDLE/LOW/OFF].
Cooling fan operates at each speed when the current flows in the cooling fan motor.
Refer to EC-59, "COOLING FAN CONTROL : System De scription (with automatic air conditioner)"
for cooling
fan operation.
EVAP CanisterINFOID:0000000009462078
EVAP canister stores the generat ed fuel vapors in the sealed fuel
tank to activated charcoals of EVAP canister when the engine is not
operating or when refueling to the fuel tank.
EVAP Canister Purge Volume Control Solenoid ValveINFOID:0000000009462079
The EVAP canister purge volume control solenoid valve uses a ON/
OFF duty to control the flow rate of fuel vapor from the EVAP canis-
ter. The EVAP canister purge volume control solenoid valve is
moved by ON/OFF pulses from the ECM. The longer the ON pulse,
the greater the amount of fuel vapor that will flow through the valve.
Engine oil temperature
[° C ( °F)] Vol tag e* (V)
Resistance (k
Ω)
–10 (14) 4.4 7.0 - 11.4 20 (68) 3.5 2.37 - 2.63
50 (122) 2.2 0.68 - 1.00
90 (194) 1.0 0.236 - 0.260
110 (230) 0.6 0.143 - 0.153
SEF012P
JPBIA5851ZZ
JMBIA0069ZZ
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COMPONENT PARTSEC-35
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EVAP Canister Vent Control ValveINFOID:0000000009462080
The EVAP canister vent control valve is located on the EVAP canis-
ter and is used to seal the canister vent.
This solenoid valve responds to signals from the ECM. When the
ECM sends an ON signal, the coil in the solenoid valve is energized.
A plunger will then move to seal the canister vent. The ability to seal
the vent is necessary for the on board diagnosis of other evaporative
emission control system components.
This solenoid valve is used only for diagnosis, and usually remains
opened.
When the vent is closed, under normal purge conditions, the evapo-
rative emission control system is depressurized and allows “EVAP
Control System” diagnosis.
EVAP Control System Pressure SensorINFOID:0000000009462081
The EVAP control system pressure sensor detects pressure in the
purge line. The sensor output voltage to the ECM increases as pres-
sure increases.
Battery Current Sensor (With Battery Temperature Sensor)INFOID:0000000009462082
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 contro l 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-10, "System Description"
.
CAUTION:
Never connect the electrical co mponent or the ground wire
directly to the battery terminal. The connection cau ses the malfunction of the power generation volt-
age variable control, and then the battery discharge may occur.
BATTERY CURRENT SENSOR
The battery current sensor is installed to the battery negative cable. The sensor measures the charging/dis-
charging current of the battery.
BATTERY TEMPERATURE SENSOR
PBIB1263E
PBIB3370E
JPBIA3262ZZ
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STRUCTURE AND OPERATIONEC-39
< SYSTEM DESCRIPTION > [QR25DE]
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On Board Refueling Vapor Recovery (ORVR)INFOID:0000000009462090
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 v apor 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 inspectio ns below, be sure to observe the following:
• Put a “CAUTION: FLAMMABL E” 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-proof containe r and put lid on securely.
- Release fuel pressure from fuel line. Refer to EC-536, "Inspection"
.
- 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 a nd check for fuel leaks at connection.
• Do not attempt to top off the fuel tank after the fuel pump nozzle shuts off automatically.
Continued refueling may cause fuel overflow, r esulting in fuel spray and possibly a fire.
JMBIA1930GB
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SYSTEMEC-41
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ECM controls the engine by various functions.
ENGINE CONTROL SYSTEM : Fail SafeINFOID:0000000009462092
NON DTC RELATED ITEM
DTC RELATED ITEM
Description
When a DTC is detected, ECM executes a mode (in the
Fail-safe mode) applicable to the DTC. The fail-safe
mode has the preset traveling control mode (accelera tor angle variation and engine output limit) and device fix
mode.
Function Reference
Multiport fuel injection system EC-43, "MULTIPORT FUEL INJECTION SYSTEM : System De-
scription (with automatic air conditioner)"
Electric ignition system
EC-48, "ELECTRIC IGNITION SYSTEM : System Description"
Intake valve timing control EC-49, "INTAKE VALVE TIMING CONTROL : System Description"
Exhaust valve timing control EC-52, "EXHAUST VALVE TIMING
CONTROL : System Descrip-tion"
Intake manifold runner control EC-53, "INTAKE MANIFOLD RUNNER CONTROL : System De-scription"
Intake manifold tuning system
EC-54, "INTAKE MANIFOLD TUNI
NG SYSTEM : System Descrip-tion"
Engine protection control EC-55, "ENGINE PROTECTION CONTROL AT LOW ENGINE OIL PRESSURE : System Description"
Fuel filler cap warning systemEC-56, "FUEL FILLER CAP WARNING SYSTEM : System De-scription"
Air conditioning cut control
EC-56, "AIR CONDITIONING CUT CONTROL : System Descrip-tion (with automatic air conditioner)"
Cooling fan controlEC-59, "COOLING FAN CONTROL :
System Description (with au-tomatic air conditioner)"
Evaporative emission system EC-62, "EVAPORATIVE EMISSION
SYSTEM : System Descrip-tion"
Automatic speed control device (ASCD) EC-63, "AUTOMATIC SPEED CONTROL DEVICE (ASCD) : Sys-tem Description"
CAN communication
EC-64, "CAN COMMUNICATION : System Description"
Detected
items Engine operating condition
in fail-safe mode Remarks Reference page
Malfunction
indicator
lamp circuit Engine speed will not rise
more than 2,500 rpm due
to the fuel cut When there is an open circuit on MIL circuit, the ECM cannot warn the
driver by lighting up MIL when there is malfunction on engine control
system.
Therefore, when electrical controlled throttle and part of ECM related
diagnoses are continuously detected as NG for 5 trips, ECM warns the
driver that engine control system malfunctions and MIL circuit is open
by means of operating fail safe function.
The fail safe function also operates when above diagnoses except MIL
circuit are detected and demands the driver to repair the malfunction. EC-517, "Compo-
nent Function
Check"
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EC-42
< SYSTEM DESCRIPTION >[QR25DE]
SYSTEM
Fail Safe Pattern
Fail Safe List
× :Applicable —: Not applicable
Fail safe mode Vehicle behavior
Traveling con-
trol mode Accelerator an-
gle variation
control ECM controls the accelerator pedal depression speed to make it slower than actual speed. This
causes a drop in accelerating performance and encourages the driver to repair malfunction.
NOTE:
ECM does not control the accelerator pedal releasing speed.
Engine output
control ECM reduces the engine output, according to the rise in engine speed. This reduces the vehicle
speed to encourage the driver to repair malfunction.
Device fix mode • This mode fixes the IVT control solenoid valve and the EVT control solenoid valve in the refer-
ence position.
• The intake manifold runner control valve motor is turned OFF (intake manifold runner control valve opens).
Pattern Fail safe mode
A Traveling control mode Accelerator angle variation control
B Engine output control
C Device fix mode
DTC No. Detected items Vehicle behavior
Pattern Others
ABC
P0011 Intake valve timing control ——×ECM activates the IVT intermediate lock control solenoid
valve to bring the cam sprocket into an intermediate lock con-
dition.
P0014
P0078 Exhaust valve timing control
——× —
P0101
P0102
P0103 Mass air flow sensor circuit
××× —
P0122
P0123
P0222
P0223
P2135 Throttle position sensor
———The ECM controls the electric throttle control actuator in reg-
ulating 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.
So, the acceleration will be poor.
P0171
P0172 Fuel injection system
×—— —
P0197
P0198 Engine oil temperature sensor
———Exhaust valve timing control does not function.
P0300
P0301
P0302
P0303
P0304 Misfire
×—— —
P0500 Vehicle speed sensor ×—— —
P050A Cold start control ×—— —
P0524 Engine oil pressure
———• ECM illuminates oil pressure warning lamp on the combina-
tion meter.
• Engine speed will not rise more than 4,000rpm due to the
fuel cut.
• Fail-safe is canceled when ignition switch OFF → ON.
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