EC-22
< SYSTEM DESCRIPTION >[QR25DE]
COMPONENT PARTS
ENGINE COMPARTMENT
Intake manifold runner control valve actuator
EC-31, "Intake Manifold Runner Control Valve"
Electric throttle control actuator
(with built in throttle position sensor and throttle control motor) EC-25, "Electric Thrott
le Control Actuator"
EVAP service port When perform the EVAP leak check, positive pressure is
delivered to the EVAP system through the EVAP service
port.
Refer to EC-537, "Inspection"
.
No. Component Function
JPBIA5840ZZ
Engine rear side Intake side
: Vehicle front
No. Component Function
Exhaust valve timing control position sensor EC-30, "Exhaust Valve Timing Control Position Sensor"
Camshaft position sensor (PHASE)EC-29, "Camshaft Position Sensor (PHASE)"
PCV valveThe positive crankcase ventilation (PCV) valve is provided
to conduct crankcase blow-by gas to the intake manifold.
Fuel injector EC-26, "Fuel Injector"
Crankshaft position sensor (POS)EC-29, "Crankshaft Position Sensor (POS)"
Knock sensorEC-33, "Knock Sensor"
Engine oil temperature sensorEC-33, "Engine Oil Temperature Sensor"
Engine oil pressure sensorEC-33, "Engine Oil Pressure Sensor"
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EC-24
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COMPONENT PARTS
A. Instrument panel area B. Periphery of pedals C. Inside fuel tank area
D. Behind fuel tank
: Vehicle front
No. Component Function Combination meter Malfunction indicator lamp (MIL)
EC-36, "Malfunction Indicator lamp (MIL)"
Information displayEC-37, "Information Display"
ASCD steering switch EC-37, "ASCD Steering Switch"
Stop lamp switch
EC-36, "Stop Lamp Switch & Brake Pedal Position Switch"
Brake pedal position switch
Accelerator pedal position sensor EC-25, "Accelerator Pedal Position Sensor"
Fuel level sensor unit and fuel pumpEC-26, "Fuel Level Sensor Unit and Fuel Pump"
Fuel tank temperature sensorEC-27, "Fuel Tank Temperature Sensor"
EVAP control system pressure sensorEC-35, "EVAP Control System Pressure Sensor"
EVAP canister vent control valve EC-35, "EVAP Canister Vent Control Valve"
EVAP canisterEC-34, "EVAP Canister"
ALBIA0806ZZ
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EC-28
< SYSTEM DESCRIPTION >[QR25DE]
COMPONENT PARTS
The mass air flow sensor is placed in the stream of intake air. It
measures the intake flow rate by measuring a part of the entire
intake flow. The MAF sensor controls the temperature of the heater
in sensing element to a certain amount. The temperature distribution
around the heater changes according to the increase in intake air
volume. The change is detected by a thermistor and the air volume
data is sent to ECM by the MAF sensor.
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 wh ich is sensitive to the change in temperature.
*: These data are reference values on the diagnosis tool.
Manifold Absolute Pressure SensorINFOID:0000000009462062
The manifold absolute pressure (MAP) sensor is placed at intake
manifold collector. It detects intake manifold pressure and sends the
voltage signal to the ECM.
The sensor uses a silicon diaphragm which is sensitive to the
change in pressure. As the pressure increases, the voltage rises.
NOTE:
The sensor is equipped, but used for trouble diagnosis only.
Engine Coolant Te mperature SensorINFOID:0000000009462063
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.
PBIA9559J
Intake air temperature
[° C ( °F)] Vo l ta g e* (V)
25 (77) 1.9 – 2.1
80 (176) 3.2 – 3.4
JPBIA4619ZZ
JPBIA5280ZZ
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EC-30
< SYSTEM DESCRIPTION >[QR25DE]
COMPONENT PARTS
ECM receives the signals as shown in the figure.
Intake Valve Timing Control Solenoid ValveINFOID:0000000009462066
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.
Intake Valve Timing Intermediate Lock Control Solenoid ValveINFOID:0000000009462067
Intake valve timing intermediate lock control solenoid valve is acti-
vated by ON/OFF signals from the ECM.
The intake valve timing intermediate lock control solenoid valve
opens/closes the path of oil pressure acting on the lock key in the
camshaft sprocket (INT).
• When the solenoid valve becomes ON, oil pressure to the lock key
is trained to perform intermediate lock.
• When the solenoid valve becomes OFF, oil pressure is acted on the lock key to release the intermediate lock.
Exhaust Valve Timing Control Position SensorINFOID:0000000009462068
Exhaust valve timing control position sensor detects the protrusion of
the signal plate installed to the exhaust camshaft front end.
This sensor signal is used for sensing a position of the exhaust cam-
shaft.
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.
JMBIA0714GB
PBIB1842E
PBIB1842E
JPBIA5847ZZ
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COMPONENT PARTSEC-31
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Exhaust Valve Timing Control Solenoid ValveINFOID:0000000009462069
Exhaust valve timing control solenoi
d valve is activated by ON/OFF
pulse duty (ratio) signals from the ECM.
The exhaust valve timing control solenoid valve changes the oil
amount and direction of flow through exhaust valve timing control
unit or stops oil flow.
The longer pulse width retards valve angle.
The shorter pulse width advances valve angle.
When ON and OFF pulse widths become equal, the solenoid valve
stops oil pressure flow to fix t he exhaust valve angle at the control
position.
Intake Manifold Runner Control ValveINFOID:0000000009462070
Intake manifold runner control valve is integrated to intake mani-
fold.
Intake manifold runner control valve is mounted each port of the
intake manifold and opened/closed by the intake manifold runner
control valve motor.
ECM controls the intake manifold runner control valve motor, accord-
ing to signals of engine speed, water temperature, etc. and stabilizes
combustion by generating a strong tunmble flow.
INTAKE MANIFOLD RUNNER CONTROL VALVE MOTOR
Intake manifold runner control valve motor is connected to the rear end of the valve shaft.
The motor opens or closes the valve by the output signal of the ECM.
INTAKE MANIFOLD RUNNER CONTROL VALVE POSITION SENSOR
Intake manifold runner control valve position sensor is connected to the front end of the valve shaft.
The sensor consists of valiable resister. It senses the valve shaft movement and feeds the voltage signals to
the ECM.
Intake Manifold Tuning ValveINFOID:0000000009462071
Intake manifold tuning valve is integrated to intake manifold.
Intake manifold tuning valve consists of valve and motor.
Intake manifold tuning valve is used to control the suction passage of
the intake manifold tuning system.
INTAKE MANIFOLD TUNING VALVE MOTOR
Intake manifold tuning valve motor is connected to the front end of the valve shaft.
The motor is operated by the ECM and it opens a nd closes the intake manifold tuning valve.
PBIB1842E
JPBIA5849ZZ
JPBIA5850ZZ
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COMPONENT PARTSEC-33
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Knock SensorINFOID:0000000009462074
The knock sensor is attached to t
he cylinder block. It senses engine
knocking using a piezoelectric el ement. 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.
Engine Oil Pressure SensorINFOID:0000000009462075
The engine oil pressure (EOP) sens or is detects engine oil pressure
and transmits a voltage signal to the ECM.
Engine Oil Temperature SensorINFOID:0000000009462076
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.
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
JSBIA0284ZZ
JSBIA0292ZZ
JPBIA5280ZZ
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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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