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-49
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The ECM receives information such as the injecti
on pulse width and camshaft position sensor (PHASE) sig-
nal. Computing this information, ignition si gnals are transmitted to the power transistor.
During the following conditions, the ignition timing is revi sed by the ECM according to the other data stored in
the ECM.
• At starting
• During warm-up
•At idle
• At low battery voltage
• During acceleration
The knock sensor retard system is designed only for emergencies. The basic ignition timing is programmed
within the anti-knocking zone, if recommended fuel is used under dry conditions. The retard system does not
operate under normal driving conditions. If engine knocking occurs, the knock sensor monitors the condition.
The signal is transmitted to the ECM. The ECM retards the ignition timing to eliminate the knocking condition.
INTAKE VALVE TIMING CONTROL
INTAKE VALVE TIMING CONTROL : System DescriptionINFOID:0000000009462096
INTAKE VALVE TIMING CONTROL
System Diagram
Input/Output Signal Chart
*: This signal is sent to the ECM through CAN communication line
JPBIA4760GB
Sensor Input signal to ECM ECM function Actuator
Crankshaft position sensor (POS) Engine speed and piston position
Intake valve
timing control Intake valve timing control
solenoid valve
Camshaft position sensor (PHASE)
Engine oil temperature sensor Engine oil temperature
Engine coolant temperature sensor Engine coolant temperature
Combination meter Vehicle speed*
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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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DIAGNOSIS SYSTEM (ECM)EC-73
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OK: Self-diagnosis is carried out and the result is OK.
NG: Self-diagnosis is carried out and the result is NG.
—: Self-diagnosis is not carried out.
When all SRT related self-diagnoses show OK results in a single cycle (Ignition OFF-ON-OFF), the SRT will
indicate “CMPLT”. → Case 1 above
When all SRT related self-diagnoses show OK results through several different cycles, the SRT will indicate
“CMPLT” at the time the respective se lf-diagnoses have at least one OK result. → Case 2 above
If one or more SRT related self-diagnoses show NG resu lts in 2 consecutive cycles, the SRT will also indicate
“CMPLT”. → Case 3 above
The table above shows that the minimum number of cycles for setting SRT as “INCMP” is the number one (1)
for each self-diagnosis (Case 1 & 2) or the number two (2) for one of self-diagnoses (Case 3). However, in
preparation for the state emissions inspection, it is unnecessary for each self-diagnosis to be executed twice
(Case 3) for the following reasons:
• The SRT will indicate “CMPLT” at the time the respective self-diagnoses have one (1) OK result.
• The emissions inspection requires “CMPLT” of the SRT only with OK self-diagnosis results.
• During SRT driving pattern, the 1st trip DTC (NG) is detected prior to “CMPLT” of SRT and the self-diagnosis
memory must be erased from the ECM after repair.
• If the 1st trip DTC is erased, all the SRT will indicate “INCMP”. NOTE:
SRT can be set as “CMPLT” together with the DTC(s) . Therefore, DTC check must always be carried out
prior to the state emission inspection even though the SRT indicates “CMPLT”.
DIAGNOSIS DESCRIPTION : Permanent Di agnostic Trouble Code (Permanent DTC)
INFOID:0000000009462117
Permanent DTC is defined in SAE J1979/ISO 15031-5 Service $0A.
ECM stores a DTC issuing a command of turning on MIL as a permanent DTC and keeps storing the DTC as
a permanent DTC until ECM judges that there is no presence of malfunction.
Permanent DTCs cannot be erased by using the erase f unction of CONSULT or Generic Scan Tool (GST) and
by disconnecting the battery to shut off power to ECM. This prevents a vehicle from passing the in-use inspec-
tion without repairing a malfunctioning part.
When not passing the in-use inspection due to more than one permanent DTC, permanent DTCs should be
erased, referring to this manual.
NOTE:
• The important items in in-use inspection are that MIL is not ON, SRT test items are set, and permanent
DTCs are not included.
• Permanent DTCs do not apply for regions that permanent DTCs are not regulated by law.
Self-diagnosis result Example
Diagnosis Ignition cycle
← ON →OFF ← ON →OFF ← ON →OFF ← ON →
All OK Case 1 P0400 OK (1) — (1) OK (2) — (2) P0402 OK (1) — (1) — (1) OK (2)
P1402 OK (1) OK (2) — (2) — (2)
SRT of EGR “CMPLT” “CMPLT” “CMPLT” “CMPLT”
Case 2 P0400 OK (1) — (1) — (1) — (1) P0402 — (0) — (0) OK (1) — (1)
P1402 OK (1) OK (2) — (2) — (2)
SRT of EGR “INCMP” “INCMP” “CMPLT” “CMPLT”
NG exists Case 3 P0400 OK OK — — P0402 — — — —
P1402 NG — NG NG
(Consecutive
NG)
(1st trip) DTC 1st trip DTC — 1st trip DTC
DTC
(= MIL ON)
SRT of EGR “INCMP” “INCMP” “INCMP” “CMPLT”
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DIAGNOSIS SYSTEM (ECM)EC-77
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In this way, all the detected malfunctions are classi
fied by their DTC numbers. The DTC 0000 refers to no mal-
function. Refer to EC-105, "DTC Index"
.
How to Erase Self-diagnostic Results
By performing this procedure, ECM memory is erased and the following diagnostic information is erased as
well.
• Diagnostic trouble codes
• 1st trip diagnostic trouble codes
• Freeze frame data
• 1st trip freeze frame data
• System readiness test (SRT) codes
• Test values
NOTE:
Also, if a battery terminal is disconnected, ECM memory is erased and the diagnostic information as listed
above is erased. (The amount of time required for eras ing may vary from a few seconds to several hours.)
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON.
5. Set ECM in “self-diagnostic results” mode.
6. The diagnostic information has been erased from the backup memory in the ECM. Fully depress the accelerator pedal and keep it depressed for more than 10 seconds.
7. Fully release the accelerator pedal, and confirm the DTC 0000 is displayed.
CONSULT FunctionINFOID:0000000009462120
FUNCTION
*: The following emission-related diagnostic information is cleared when the ECM memory is erased.
• Diagnostic trouble codes
• 1st trip diagnostic trouble codes
• Freeze frame data
• 1st trip freeze frame data
• System readiness test (SRT) codes
•Test values
SELF-DIAGNOSTIC RESULT MODE
Self Diagnostic Item
Regarding items of DTC and 1st trip DTC, refer to EC-105, "DTC Index".)
How to Read DTC and 1st Trip DTC
DTCs and 1st trip DTCs related to the malfunction are displayed in “self-diag results”.
• When ECM detects a 1st trip DTC, 1t” is displayed for “TIME”.
• When ECM has detected a current DTC, “0” is displayed for “TIME”.
• If “TIME” is neither “0” nor “1t”, the DTC occurred in the past and ECM shows the number of times the vehi-
cle has been driven since the last detection of the DTC.
Diagnostic test mode Function
Self Diagnostic Result Self-diagnostic results such as 1st trip DTC, DTC and 1st trip freeze frame data or freeze frame data
can be read and erased quickly.*
Data Monitor Input/Output data in the ECM can be read.
Work support This mode enables a technician to adjust some devices faster and more accurately by following the in-
dications on the CONSULT screen.
Active Test Diagnostic Test Mode in which CONSULT drives some actuators apart from the ECMs and also shifts
some parameters in a specified range.
ECU Identification ECM part number can be read.
DTC Work Support The status of system monitoring tests and the self-diagnosis status/results can be confirmed.
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DIAGNOSIS SYSTEM (ECM)EC-79
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OMonitored item Unit Monitor Item
Selection
Description Remarks
ECU
IN-
PUT
SIG-
NALS MAIN
SIG-NAL
S
ENG SPEED rpm ×ו Indicates the engine speed computed
from the signal of the crankshaft position
sensor (POS) and camshaft position sen-
sor (PHASE). • Accuracy becomes poor if en-
gine speed drops below the
idle rpm.
• If the signal is interrupted while
the engine is running, an ab-
normal value may be indicat-
ed.
MAS A/F SE-B1 V ×ו The signal voltage of the mass air flow
sensor is displayed. • When the engine is stopped, a
certain value is indicated.
• When engine is running, spec- ification range is indicated in
“SPEC”.
B/FUEL SCHDL ms ×ו “Base fuel schedule” indicates the fuel in-
jection pulse width programmed into
ECM, prior to any learned on board cor-
rection. • When engine is running, spec-
ification range is indicated in
“SPEC”.
A/F ALPHA-B1 % • The mean value of the air-fuel ratio feed-
back correction factor per cycle is indicat-
ed. • When the engine is stopped, a
certain value is indicated.
• When engine is running, spec-
ification range is indicated in
“SPEC”.
• This data also includes the
data for the air-fuel ratio learn-
ing control.
COOLAN TEMP/S °C or °F ×× • The engine coolant temperature (deter-
mined by the signal voltage of the engine
coolant temperature sensor) is dis-
played. • When the engine coolant tem-
perature sensor is open or
short-circuited, ECM enters
fail-safe mode. The engine
coolant temperature deter-
mined by the ECM is dis-
played.
A/F SEN1 (B1) V ×ו The A/F signal computed from the input
signal of the air fuel ratio (A/F) sensor 1
is displayed.
HO2S2 (B1) V ×ו The signal voltage of the heated oxygen
sensor 2 is displayed.
HO2S2 MNTR(B1) RICH/LEAN ו Display of heated oxygen sensor 2 sig-
nal.
- RICH: means the amount of oxygen after
three way catalyst is relatively small.
- LEAN: means the amount of oxygen after three way catalyst is relatively large. • When the engine is stopped, a
certain value is indicated.
VHCL SPEED SE km/h or mph ×ו The vehicle speed computed from the
vehicle speed signal sent from combina-
tion meter is displayed.
BATTERY VOLT V • The power supply voltage of ECM is dis-
played.
ACCEL SEN 1
V• The accelerator pedal position sensor
signal voltage is displayed. • ACCEL SEN 2 signal is con-
verted by ECM internally.
Thus, it differs from ECM ter-
minal voltage signal.
ACCEL SEN 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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