EC-554
< SYSTEM DESCRIPTION >[VQ35DE]
COMPONENT PARTS
Camshaft Position Sensor (PHASE)
INFOID:0000000009462485
The camshaft position sensor (P HASE) senses the retraction of
intake camshaft to identify a particular cylinder. The camshaft posi-
tion sensor (PHASE) sens es 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.
ECM receives the signals as shown in the figure.
Cooling FanINFOID:0000000009462486
DESCRIPTION
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].
Refer to EC-575, "COOLING FAN CONTRO L : System Description"
for cooling fan operation.
COOLING FAN MOTOR RELAY
Power supply for the cooling fan motor is provided via cooling fan motor relay.
Crankshaft Position Sensor (POS)INFOID:0000000009462487
The crankshaft position sensor (POS) is located on the oil pan facing
the gear teeth (cogs) of the signal pl ate. 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.
JMBIA0064ZZ
JMBIA0001GB
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COMPONENT PARTSEC-555
< SYSTEM DESCRIPTION > [VQ35DE]
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ECM receives the signals as shown in the figure.
ECMINFOID:0000000009462488
• ECM (Engine Control Module) controls the engine.
• 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 ActuatorINFOID:0000000009462489
OUTLINE
Electric throttle control actuator cons ists 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.
JMBIA0001GB
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EC-556
< SYSTEM DESCRIPTION >[VQ35DE]
COMPONENT PARTS
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 MountINFOID:0000000009462490
In the idle range, ECM turns OFF the electronically- controlled engine mount control solenoid valve and applies
manifold pressure to the electronically-controlled engi ne mount. This decreases damping force of the electron-
ically-controlled engine mount and absorbs vibrations trav eling from the engine to the body for improving the
quietness.
In the driving range, ECM turns ON the electronicall y-controlled engine mount control solenoid valve and cuts
manifold pressure applied on the electronically-controlled engine mount. This increases damping force of the
electronically-controlled engine mount and r educes vibrations generated during driving.
Engine Coolant Temperature SensorINFOID:0000000009462491
The engine coolant temperature sensor is used to detect the engine
coolant temperature. The sensor modifies a voltage signal from the
ECM. The modified signal returns to the ECM as the engine coolant
temperature input. The sensor uses a thermistor which is sensitive to
the change in temperature. The elec trical resistance of the ther-
mistor decreases as temperature increases.
*: These data are reference values and are measured between ECM terminals.
PBIB0145E
SEF594K
Engine coolant 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) 0.9 0.236 - 0.260
SEF012P
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COMPONENT PARTSEC-557
< SYSTEM DESCRIPTION > [VQ35DE]
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Engine Oil Pressure SensorINFOID:0000000009462492
The engine oil pressure (EOP) sens
or is detects engine oil pressure
and transmits a voltage signal to the ECM.
Engine Oil Temperature SensorINFOID:0000000009462493
The engine oil temperature sensor is used to detect the engine oil
temperature. The sensor modifies a voltage signal from the ECM.
The modified signal returns to the ECM as the engine oil tempera-
ture 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.
EVAP CanisterINFOID:0000000009462494
The fuel vapor in the sealed fuel tank is led into t he EVAP canister which contains activated carbon and the
vapor is stored there when the engine is not oper ating or when refueling to the fuel tank.
For details, refer to EC-580, "EVAPORATIVE EMISSION SYSTEM : System Description"
.
EVAP Canister Purge Volume Control Solenoid ValveINFOID:0000000009462495
The EVAP canister purge volume control solenoid valve is used to
control the flow rate of fuel v apor from the EVAP canister. 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.
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Engine oil temperature
[° C ( °F)] Vo l ta g 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) 0.9 0.236 - 0.260
110 (230) 0.6 0.143 - 0.153
SEF012P
PBIB3489E
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EC-558
< SYSTEM DESCRIPTION >[VQ35DE]
COMPONENT PARTS
EVAP Canister Vent Control Valve
INFOID:0000000009462496
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:0000000009462497
The EVAP control system pressure s ensor detects pressure in the
purge line. The sensor output voltage to the ECM increases as pres-
sure increases.
Fuel InjectorINFOID:0000000009462498
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 Pump (With Fuel Tank Temperature Sensor)
INFOID:0000000009462499
FUEL PUMP
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.
JSBIA1337GB
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COMPONENT PARTSEC-559
< SYSTEM DESCRIPTION > [VQ35DE]
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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 SENSOR
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 95 (Fuel tank temperature sensor) and ground.
Heated Oxygen Sensor 2INFOID:0000000009462500
DESCRIPTION
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 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 oxygen 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 oxygen sensor 2 heater corresponding to the engine speed,
amount of intake air and engine coolant temperature.
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 .
Fluid temperature
[° C ( °F)] Voltage*
(V) Resistance
(kΩ)
20 (68) 3.5 2.3 - 2.7
50 (122) 2.2 0.79 - 0.90
SEF012P
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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
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EC-560
< SYSTEM DESCRIPTION >[VQ35DE]
COMPONENT PARTS
Ignition Coil (With Power Transistor)
INFOID:0000000009462501
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.
Intake Valve Timing Control Solenoid ValveINFOID:0000000009462502
Intake valve timing control solenoid valve is activated by ON/OFF
pulse duty (ratio) signals from the ECM.
The intake valve timing control solenoid valve changes the oil
amount and direction of flow through intake valve timing control unit
or stops oil flow.
The longer pulse width advances valve angle.
The shorter pulse width retards valve angle.
When ON and OFF pulse widths become equal, the solenoid valve
stops oil pressure flow to fix the intake valve angle at the control
position.
Knock SensorINFOID:0000000009462503
The knock sensor is attached to t he cylinder block. It senses engine
knocking using a piezoelectric element. A knocking vibration from
the cylinder block is sensed as vibrational pressure. This pressure is
converted into a voltage signal and sent to the ECM.
Malfunction Indicator lamp (MIL)INFOID:0000000009462504
Malfunction Indicator lamp (MIL) is located on the combination
meter.
MIL will illuminate when the ignition switch is turned ON without the
engine running. This is a bulb check.
When the engine is started, MIL should turn OFF. If the MIL remains
illuminated, the on board diagnosti c system has detected an engine
system malfunction.
For details, refer to EC-590, "Diagnosis Description"
.
Mass Air Flow Sensor (With In take Air Temperature Sensor)INFOID:0000000009462505
MASS AIR FLOW SENSOR
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COMPONENT PARTSEC-561
< SYSTEM DESCRIPTION > [VQ35DE]
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The mass air flow sensor (1) is plac
ed in the stream of intake air. It
measures the intake flow rate by measuring a part of the entire
intake flow. The mass air flow sens or controls the temperature of the
hot wire to a certain amount. The heat generated by the hot wire is
reduced as the intake air flows around it. The more air, the greater
the heat loss.
Therefore, the electric current supplied to hot wire is changed to
maintain the temperature of the hot wire as air flow increases. The
ECM detects the air flow by means of this current change.
INTAKE AIR TEMPERATURE SENSOR
The intake air temperature sensor is built-into mass air flow sensor. The sensor detects intake air temperature
and transmits a signal to the ECM.
The temperature sensing unit uses a thermistor which is sensitive to the change in temperature. Electrical
resistance of the thermistor decreases in response to the temperature rise.
*: These data are reference values and are measured between ECM terminals.
Oil Pressure Warning LampINFOID:0000000009462506
Oil pressure warning lamp is located on the combination meter.
It indicates the low pressure of the engine oil and the malfunction of
the engine oil pressure system.
Combination meter turns the oil pressure warning lamp ON/OFF
according to the oil pressure warning lamp signal received from
ECM via CAN communication.
For details, refer to EC-583, "ENGINE PROTECTION CONTROL AT
LOW ENGINE OIL PRESSURE : System Description".
Power Valve Actuator 1 and 2INFOID:0000000009462507
The power valves are used to control the suction pa ssage of the variable induction air control system. They
are set in the fully closed or fully opened position by t he power valve actuators operated by the vacuum stored
in the vacuum tank. The vacuum to power valve actuat ors is controlled by the VIAS control solenoid valves.
PBIA9559J
Intake air temperature
[° C ( °F)] Voltag e* (V)
Resistance (k
Ω)
25 (77) 3.3 1.800 - 2.200
80 (176) 1.2 0.283 - 0.359
SEF012P
PBIA8559J
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