EC-30
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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.
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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.
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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
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EC-34
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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
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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
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EC-36
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COMPONENT PARTS
Battery temperature sensor is int
egrated in battery current sensor.
The sensor measures temperature around the battery.
The electrical resistance of the t hermistor decreases as temperature
increases.
*: These data are reference values and are measured between battery temperature
sensor signal terminal and sensor ground.
Malfunction Indicator lamp (MIL)INFOID:0000000009462083
The Malfunction Indicator lamp (MIL) is located on the combination
meter.
The MIL will illuminate when the ignition switch is turned ON without
the engine running. This is a bulb check.
When the engine is started, the MI L should turn OFF. If the MIL
remains illuminated, the on board diagnostic system has detected an
engine system malfunction.
For details, refer to EC-74, "DIAGNOSIS DESCRIPTION : Malfunc-
tion Indicator Lamp (MIL)".
Oil Pressure Warning LampINFOID:0000000009462084
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-55, "ENGINE PROTECTION CONTROL AT
LOW ENGINE OIL PRESSURE : System Description".
Refrigerant Pressure SensorINFOID:0000000009462085
The refrigerant pressure sensor is installed at the c ondenser of the air conditioner system. The sensor uses an
electrostatic volume pressure transducer to convert refrigerant pressure to voltage. The voltage signal is sent
to ECM, and ECM controls cooling fan system.
Stop Lamp Switch & Brake Pedal Position SwitchINFOID:0000000009462086
Stop lamp switch and brake pedal position switch are installed to brake pedal bracket.
ECM detects the state of the brake pedal by those two types of input (ON/OFF signal).
Temperature [°C ( °F)]
Vo l ta g e* (V) Resistance (k
Ω)
25 (77) 3.333 1.9 - 2.1
90 (194) 0.969 0.222 - 0.258
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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
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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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