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Nissan Pathfinder. Manual - part 428

EC-18

< SYSTEM DESCRIPTION >

[VQ35DE]

COMPONENT PARTS

Accelerator Pedal Position Sensor

INFOID:0000000009178003

The accelerator pedal position sensor is installed on the upper end

of the accelerator pedal assembly. The sensor detects the accelera-

tor position and sends a signal to the ECM.

Accelerator pedal position sensor has two sensors. These sensors

are a kind of potentiometers which transform the accelerator pedal

position into output voltage, and emit the voltage signal to the ECM.

In addition, these sensors detect the opening and closing speed of

the accelerator pedal and feed 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 the engine operation such as fuel cut.

Air Fuel Ratio (A/F) Sensor 1

INFOID:0000000009178004

DESCRIPTION

The air fuel ratio (A/F) sensor 1 is a planar one-cell limit current sen-

sor. The sensor element of the A/F sensor 1 is composed an elec-

trode 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 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 hydrocar-

bon density in rich.

Fuel level sensor unit and fuel pump (with fuel tank temper-
ature sensor)

EC-24, "Fuel Level Sensor Unit and Fuel Pump (With Fuel Tank
Temperature Sensor)"

Refer to

FL-6, "Exploded View"

for detailed installation location.

EVAP control system pressure sensor

EC-23, "EVAP Control System Pressure Sensor"

EVAP canister vent control valve

EC-23, "EVAP Canister Vent Control Valve"

EVAP canister

EC-23, "EVAP Canister"

No.

Component

Function

JPBIA4615ZZ

PBIB1741E

JMBIA0112GB

COMPONENT PARTS

EC-19

< SYSTEM DESCRIPTION >

[VQ35DE]

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 800

°C (1,472°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 sensor 1 element within the specified range.

ASCD Steering Switch

INFOID:0000000009178005

ASCD steering switch has variant values of electrical resistance for each button. ECM reads voltage variation

of switch, and determines which button is operated.

Battery Current Sensor (With Battery Temperature Sensor)

INFOID:0000000009178006

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 integrated in battery current sensor.

The sensor measures temperature around the battery.

The electrical resistance of the thermistor decreases as temperature

increases.

<Reference data>

*: These data are reference values and are measured between bat-

tery temperature sensor signal terminal and sensor ground.

Camshaft Position Sensor (PHASE)

INFOID:0000000009178007

The camshaft position sensor (PHASE) senses the retraction of

intake camshaft to identify a particular cylinder. The camshaft posi-

tion sensor (PHASE) senses the piston position.

When the crankshaft position sensor (POS) system becomes inoper-

ative, the camshaft position sensor (PHASE) provides various con-

trols of engine parts instead, utilizing timing of cylinder identification

signals.

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.

JPBIA5446GB

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

EC-20

< SYSTEM DESCRIPTION >

[VQ35DE]

COMPONENT PARTS

ECM receives the signals as shown in the figure.

Cooling Fan Motor & Cooling Fan Control Module

INFOID:0000000009178008

COOLING FAN MOTOR

Cooling fan motor receives cooling fan motor operating voltage from cooling fan control module. The revolu-

tion speed of cooling fan motor is controlled by duty cycle of the voltage.

COOLING FAN CONTROL MODULE

Cooling fan control module receives ON/OFF pulse duty signal from IPDM E/R. Corresponding to this ON/OFF

pulse duty signal, cooling fan control module sends cooling fan motor operating voltage to cooling fan motor.

The revolution speed of cooling fan motor is controlled by duty cycle of the voltage.

Crankshaft Position Sensor (POS)

INFOID:0000000009178009

The crankshaft position sensor (POS) is located on the oil pan facing

the gear teeth (cogs) of the signal plate. It detects the fluctuation of

the engine revolution.

The sensor consists of a permanent magnet and Hall IC.

When the 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.

The ECM receives the voltage signal and detects the fluctuation of

the engine revolution.

ECM receives the signals as shown in the figure.

ECM

INFOID:0000000009178010

• ECM (Engine Control Module) controls the engine.

JMBIA0001GB

JMBIA0062ZZ

JMBIA0001GB

COMPONENT PARTS

EC-21

< SYSTEM DESCRIPTION >

[VQ35DE]

• ECM consists of a microcomputer and connectors for signal input

and output and for power supply.

• Battery voltage is supplied to the ECM even when the ignition

switch is turned OFF for the ECM memory function of the DTC

memory, the air-fuel ratio feedback compensation value memory,

the idle air volume learning value memory, etc.

Electric Throttle Control Actuator

INFOID:0000000009178011

OUTLINE

Electric throttle control actuator consists of throttle body, throttle valve, throttle control motor and throttle posi-

tion sensor.

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 motor 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.

Electronic Controlled Engine Mount

INFOID:0000000009178012

In the idle range, ECM turns OFF the electronically-controlled engine mount control solenoid valve and applies

manifold pressure to the electronically-controlled engine mount. This decreases damping force of the electron-

ically-controlled engine mount and absorbs vibrations traveling from the engine to the body for improving the

quietness.

PBIA9222J

JSBIA0270GB

PBIB0145E

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