STRUCTURE AND OPERATIONEC-39
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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
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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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SYSTEMEC-55
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Intake Manifold Tuning Valve Operating Condition
ECM opens the intake manifold tuning valve when all of the following conditions are satisfied.
• Engine speed: 5,000 rpm or more
• Engine coolant temperature: -30 °C (-22 °F) or more
• Battery voltage: 16 V or less
ENGINE PROTECTION CONTROL AT LOW ENGINE OIL PRESSURE
ENGINE PROTECTION CONTROL AT LOW ENGINE OIL PRESSURE : System De-
scription
INFOID:0000000009462100
SYSTEM DIAGRAM
INPUT/OUTPUT SIGNAL CHART
SYSTEM DESCRIPTION
• The engine protection control at low engine oil pressure warns the driver of a decrease in engine oil pres-
sure by the oil pressure warning lamp a before the engine becomes damaged.
• When detecting a decrease in engine oil pressure at an engine speed less than 1,000 rpm, ECM transmits an oil pressure warning lamp signal to the combination meter.The combination meter turns ON the oil pres-
sure warning lamp, according to the signal.
*: When detecting a normal engine oil pressure, ECM turns OFF the oil pressure warning lamp.
FUEL FILLER CAP WARNING SYSTEM
JPBIA4922GB
Sensor Input signal to ECM ECM function Actuator
Engine oil pressure sensor Engine pressure Engine protection control
• Oil pressure warning lamp
signal
•FUel cut control Combination meter
• Oil pressure warning lamp
Crankshaft position sensor
(POS) Engine speed
Engine oil temperature sensor Engine oil temperature
Decrease in engine oil pressure Engine speed Combination meter
Fuel cut
Oil pressure warning lamp
Detection Less than 1,000 rpm ON* NO
1,000 rpm or more ON YES
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EC-62
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SYSTEM
EVAPORATIVE EMISSION SYSTEM : System Description
INFOID:0000000009462106
SYSTEM DIAGRAM
INPUT/OUTPUT SIGNAL CHART
*1: ECM determines the start signal status by the signals of engine speed and battery voltage.
*2: This signal is sent to the ECM through CAN communication line.
JPBIA4896GB
Sensor Input signal to ECM ECM function Actuator
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE) Engine speed*
1
EVAP canister
purge flow control EVAP canister purge vol-
ume control solenoid valve
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Battery Battery voltage*
1
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Air fuel ratio (A/F) sensor 1 Density of oxygen in exhaust gas
(Mixture ratio fe edback signal)
Fuel tank temperature sensor Fuel temperature in fuel tank
EVAP control system pressure sensor Pressure in purge line
Combination meter Vehicle speed*
2
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EC-80
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DIAGNOSIS SYSTEM (ECM)
TP SEN 1-B1
V××
• The throttle position sensor signal volt-age is displayed. • TP SEN 2-B1 signal is convert-
ed by ECM internally. Thus, it
differs from ECM terminal volt-
age signal.
TP SEN 2-B1
××
FUEL T/TMP SE °C or °F • The fuel temperature (determined by the
signal voltage of the fuel tank tempera-
ture sensor) is displayed.
EVAP SYS PRES V • The signal voltage of EVAP control sys-
tem pressure sensor is displayed.
FUEL LEVEL SE V ו The signal voltage of the fuel level sensor
is displayed.
START SIGNAL On/Off • Indicates start signal status [ON/OFF]
computed by the ECM according to the
signals of engine speed and battery volt-
age. • After starting the engine, [OFF]
is displayed regardless of the
starter signal.
CLSD THL POS On/Off ×ו Indicates idle position [ON/OFF] comput-
ed by ECM according to the accelerator
pedal position sensor signal.
AIR COND SIG On/Off ×ו Indicates [ON/OFF] condition of the air
conditioner switch as determined by the
air conditioner signal.
PW/ST SIGNAL On/Off ×ו [ON/OFF] condition of the power steering
system (determined by the signal sent
from EPS control unit) is indicated.
LOAD SIGNAL On/Off ×ו Indicates [ON/OFF] condition from the
electrical load signal.
- On: Rear window defogger switch is ON and/or lighting switch is in 2nd position.
- Off: Both rear window defogger switch
and lighting switch are OFF.
IGNITION SW On/Off ×ו Indicates [ON/OFF] condition from igni-
tion switch signal.
HEATER FAN SW On/Off ו Indicates [ON/OFF] condition from the
heater fan switch signal.
BRAKE SW On/Off • Indicates [ON/OFF] condition from the
stop lamp switch signal.
INJ PULSE-B1 msec • Indicates the actual fuel injection pulse
width compensated by ECM according to
the input signals. • When the engine is stopped, a
certain computed value is indi-
cated.
IGN TIMING BTDC ו Indicates the ignition timing computed by
ECM according to the input signals. • When the engine is stopped, a
certain value is indicated.
CAL/LD VALUE % • “Calculated load value” indicates the val-
ue of the current air flow divided by peak
air flow.
MASS AIRFLOW g/s • Indicates the mass air flow computed by
ECM according to the signal voltage of
the mass air flow sensor.
Monitored item Unit
Monitor Item
Selection
Description Remarks
ECU
IN-
PUT
SIG-
NALS MAIN
SIG-
NAL S
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DIAGNOSIS SYSTEM (ECM)EC-83
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LO SPEED CUT Non/Cut
• Indicates the vehicle cruise condition.
- Non: Vehicle speed is maintained at the ASCD set speed.
- Cut: Vehicle speed decreased to exces- sively low, and ASCD operation is cut off.
AT OD MONITOR On/Off • Indicates [ON/OFF] condition of CVT O/
D according to the input signal from the
TCM.
AT OD CANCEL On/Off • Indicates [ON/OFF] condition of CVT O/
D cancel request signal.
CRUISE LAMP On/Off • Indicates [ON/OFF]
condition of CRUISE
lamp determined by the ECM according
to the input signals.
SET LAMP On/Off • Indicates [ON/OFF] condition of SET
lamp determined by the ECM according
to the input signals.
ALT DUTY % • Indicates the duty ratio of the power gen-
eration command value. The ratio is calu-
culated by ECM based on the battery
current sensor signal.
BAT CUR SEN mV • The signal voltage of battery current sen-
sor is displayed.
A/F ADJ-B1 — • Indicates the correction of factor stored in
ECM. The factor is calculated from the
difference between the target air-fuel ra-
tio stored in ECM and the air-fuel ratio
calculated from A/F sensor 1 signal.
TUMBLE POS SEN V • The intake manifold runner control valve
position sensor signal voltage is dis-
played.
P/N POSI SW On/Off ×ו Indicates [ON/OFF] condition from the
park/neutral position (PNP) signal.
INT/A TEMP SE °C or °F ×× • The intake air temperature (determined
by the signal voltage of the intake air tem-
perature senso r) is indicated.
AC PRESS SEN V • The signal voltage from the refrigerant
pressure sensor is displayed.
VTC DTY EX B1 % • The control value of the exhaust valve
timing control solenoid valve (determined
by ECM according to the input signals) is
indicated.
• The advance angle becomes larger as the value increases.
EVAP LEAK DIAG YET/CMPLT • Indicates the condition of EVAP leak di-
agnosis.
YET: EVAP leak diagnosis has not been
performed yet.
CMPLT: EVAP leak diagnosis has been
performed successfully.
Monitored item Unit
Monitor Item
Selection
Description Remarks
ECU
IN-
PUT
SIG-
NALS MAIN
SIG-
NAL S
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DIAGNOSIS SYSTEM (ECM)EC-85
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WORK SUPPORT MODE
Work Item
*: This function is not necessary in the usual service procedure.
ACTIVE TEST MODE
Test Item
Work item Condition Usage
IDLE AIR VOL LEARN • The idle air volume that keeps the engine within the spec- ified range is memorized in ECM. When learning the idle air volume
EVAP SYSTEM CLOSE Close the EVAP canister vent control valve in order to make
EVAP system close under the following conditions.
• Ignition switch ON
• Engine not running
• Ambient temperature is above 0 °C (32 °F).
• No vacuum and no high pressure in EVAP system
• Fuel tank temp is more than 0 °C (32 °F).
• Within 10 minutes after starting “EVAP SYSTEM CLOSE”
• When trying to execute “EVAP SYSTEM CLOSE” under the condition except above, CONSULT will discontinue it
and display appropriate instruction.
NOTE:
When starting engine, CONSULT may display “BAT-
TERY VOLTAGE IS LOW. CHARGE BATTERY”, even in
when using a charged battery. When detecting EVAP vapor leak
in the EVAP system
FUEL PRESSURE RELEASE • Fuel pump will st op by touching “START” during idling.
Crank a few times after engine stalls. When releasing fuel pressure from
fuel line
TARGET IGN TIM ADJ* • Idle condition When adjusting target ignition tim- ing
TARGET IDLE RPM ADJ* • Idle condition When setting target idle speed
VIN REGISTRATION • In this mode , VIN is registered in ECM. When registering VIN in ECM
SELF-LEARNING CONT • The coefficient of self-learning control mixture ratio returns to the original coefficient. When clearing mixture ratio self-
learning value
CLSD THL POS LEARN • Ignition on and engine stopped. When learning the throttle valve
closed position
SAVING DATA FOR REPLC CPU In th is mode, save data that is in ECM. When ECM is replaced.
WRITING DATA FOR REPLC CPU In this mode, write data stored by “SAVE DATA FOR CPU
REPLC” in work support mode to ECM. When ECM is replaced.
Test item Condition Judgment Check item (Remedy)
FUEL INJECTION • Engine: Return to the original
trouble condition
• Change the amount of fuel injec- tion using CONSULT. If trouble symptom disappears, see
CHECK ITEM. • Harness and connectors
• Fuel injector
• Air fuel ratio (A/F) sensor 1
ENG COOLANT
TEMP • Engine: Return to the original
trouble condition
• Change the engine coolant tem- perature using CONSULT. If trouble symptom disappears, see
CHECK ITEM. • Harness and connectors
• Engine coolant temperature
sensor
• Fuel injector
PURG VOL CONT/V • Engine: After warming up, run en-
gine at 1,500 rpm.
• Change the EVAP canister purge volume control solenoid valve
opening percent using CON-
SULT. Engine speed changes according
to the opening percent. • Harness and connectors
• Solenoid valve
FUEL/T TEMP SEN • Change the fuel tank temperature using CONSULT.
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