EC-36
< SYSTEM DESCRIPTION >[QR25DE]
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
SEF012P
JSBIA1315ZZ
PBIA8559J
PBIB2657E
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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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DIAGNOSIS SYSTEM (ECM)EC-67
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DIAGNOSIS SYSTEM (ECM)
DIAGNOSIS DESCRIPTION
DIAGNOSIS DESCRIPTION : 1s
t Trip Detection Logic and Two Trip Detection Logic
INFOID:0000000009462112
When a malfunction is detected for the first time, 1st tr ip DTC and 1st trip Freeze Frame data are stored in the
ECM memory. The MIL will not illuminate at this stage. <1st trip>
If the same malfunction is detected again during the next drive, the DTC and Freeze Frame data are stored in
the ECM memory, and the MIL illuminates. The MIL illu minates at the same time when the DTC is stored.
<2nd trip> The “trip” in the “Two Trip Detection Logic” means a driving mode in which self-diagnosis is per-
formed during vehicle operation. Specific on board diagnosti c items will cause the ECM to illuminate or blink
the MIL, and store DTC and Freeze Frame data, even in the 1st trip, as shown below.
×: Applicable —: Not applicable
DIAGNOSIS DESCRIPTION : DTC and Freeze Frame DataINFOID:0000000009462113
DTC AND 1ST TRIP DTC
The 1st trip DTC (whose number is the same as the DT C number) is displayed for the latest self-diagnostic
result obtained. If the ECM memory was cleared previously , and the 1st trip DTC did not recur, the 1st trip DTC
will not be displayed.
If a malfunction is detected during the 1st trip, the 1st trip DTC is saved in the ECM memory. The MIL will not
light up (two trip detection logic). If the same malfunc tion is not detected in the 2nd trip (meeting the required
driving pattern), the 1st trip DTC is cleared from the ECM memory. If the same malfunction is detected in the
2nd trip, both the 1st trip DTC and DTC are saved in t he ECM memory and the MIL lights up. In other words,
the DTC is stored in the ECM memory and the MIL light s up when the same malfunction occurs in two consec-
utive trips. If a 1st trip DTC is stored and a non-diagnostic operation is performed between the 1st and 2nd
trips, only the 1st trip DTC will continue to be stored. Fo r malfunctions that blink or light up the MIL during the
1st trip, the DTC and 1st trip DTC are stored in the ECM memory.
For malfunctions in which 1st trip DTCs are displayed, refer to EC-105, "DTC Index"
. These items are
required by legal regulations to c ontinuously monitor the system/component . In addition, the items monitored
non-continuously are also displayed on CONSULT.
1st trip DTC is specified in Service $07 of SAE J1979/ ISO 15031-5. 1st trip DTC detection occurs without illu-
minating the MIL and therefore does not warn the driver of a malfunction.
When a 1st trip DTC is detected, check, print out or write down and erase (1st trip) DTC and Freeze Frame
data as specified in Work Flow procedure Step 2, refer to EC-165, "Work Flow"
. Then perform DTC Confirma-
tion Procedure or Component Function Check to try to duplicate the malfunction. If the malfunction is dupli-
cated, the item requires repair.
FREEZE FRAME DATA AND 1ST TRIP FREEZE FRAME DATA
The ECM records the driving conditions such as fuel system status, calculated load value, engine coolant tem-
perature, short term fuel trim, long term fuel trim, engi ne speed, vehicle speed, absolute throttle position, base
fuel schedule and intake air temperature at the moment a malfunction is detected.
Data which are stored in the ECM memory, along with the 1st trip DTC, are called 1st trip freeze frame data.
The data, stored together with the DTC data, are called freeze frame data and displayed on CONSULT or
GST. The 1st trip freeze frame data c an only be displayed on the CONSULT screen.
Items MIL DTC 1st trip DTC
1st trip 2nd trip 1st trip
displaying 2nd trip
displaying 1st trip
displaying 2nd trip
display- ing
Blinking Illuminat-
ed Blinking Illuminat-
ed
Misfire (Possible three way catalyst
damage) — DTC: P0300 – P0304
is being detected ×
———— — ×—
Misfire (Possible three way catalyst
damage) — DTC: P0300 – P0304
is being detected ——
×—— ×——
One trip detection diagnoses (Re-
fer to EC-105, "DTC Index"
.) —
×—— ×———
Except above — — — ×— ×× —
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EC-72
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DIAGNOSIS SYSTEM (ECM)
Calculated load value: (Calculated load value in the freeze frame data) x (1
±0.1) [%]
Engine coolant temperature condition:
• When the freeze frame data shows lower than 70 °C (158 °F), engine coolant temperature should be lower
than 70 °C (158 °F).
• When the freeze frame data shows higher than or equal to 70 °C (158 °F), engine coolant temperature should
be higher than or equal to 70 °C (158 °F).
NOTE:
• When the same malfunction is detected regardless of t he above vehicle conditions, reset the counter of driv-
ing pattern C.
• When the above conditions are satisfied without detecting t he same malfunction, reset the counter of driving
pattern C.
• The 1st trip DTC will be cleared when C counter is c ounted once without the same malfunction after DTC is
stored in ECM.
DRIVING PATTERN D
Driving pattern D means a trip satisfying the following conditions.
• The state of driving at 40 km/h (25 MPH) reaches 300 seconds or more in total.
• Idle speed lasts 30 seconds or more.
• A lapse of 600 seconds or more after engine start.
NOTE:
• When the same malfunction is detected regardless of driv ing conditions, reset the counter of driving pattern
D.
• When the above conditions are satisfied without detecting t he same malfunction, reset the counter of driving
pattern D.
DIAGNOSIS DESCRIPTION : System Readiness Test (SRT) CodeINFOID:0000000009462116
System Readiness Test (SRT) code is spec ified in Service $01 of SAE J1979/ISO 15031-5.
As part of an enhanced emissions test for Inspection & Ma intenance (I/M), certain states require the status of
SRT be used to indicate whether the ECM has completed self-diagnosis of major emission systems and com-
ponents. Completion must be verified in order for the emissions inspection to proceed.
If a vehicle is rejected for a State emissions inspec tion due to one or more SRT items indicating “INCMP”, use
the information in this Service Manual to set the SRT to “CMPLT”.
In most cases the ECM will automatically complete its self-diagnosis cycle during normal usage, and the SRT
status will indicate “CMPLT” for each application system . Once set as “CMPLT”, the SRT status remains
“CMPLT” until the self-diagnosis memory is erased.
Occasionally, certain portions of the self-diagnostic test may not be completed as a result of the customer's
normal driving pattern; the SRT will indicate “INCMP” for these items.
NOTE:
The SRT will also indicate “INCMP” if the self-diagnosis memory is erased for any reason or if the ECM mem-
ory power supply is interrupted for several hours.
If, during the state emissions inspection, the SRT indica tes “CMPLT” for all test items, the inspector will con-
tinue with the emissions test. However, if the SRT indi cates “INCMP” for one or more of the SRT items the
vehicle is returned to the customer untested.
NOTE:
If permanent DTC is stored or MIL illuminates during t he state emissions inspection, the vehicle is also
returned to the customer untested even though the SRT indi cates “CMPLT” for all test items. therefore, it is
important to check SRT (“CMPLT”), DTC (No DTCs) and permanent DTC (No permanent DTC) before the
inspection.
SRT SET TIMING
SRT is set as “CMPLT” after self-diagnosis has been performed one or more times. Completion of SRT is
done regardless of whether the result is OK or NG. T he set timing is different between OK and NG results and
is shown in the table below.
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EC-74
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DIAGNOSIS SYSTEM (ECM)
PERMANENT DTC SET TIMING
The setting timing of permanent DTC is stored in EC
M with the lighting of MIL when a DTC is confirmed.
DIAGNOSIS DESCRIPTION : Malfunction Indicator Lamp (MIL)INFOID:0000000009462118
When emission-related ECU detects a malfunction in the emission
control systems components and/or the powertrain control compo-
nents (which affect vehicle emissions), it turns on/blinks MIL to
inform the driver that a malfunction has been detected.
1. The MIL illuminates when ignition switch is turned ON (engine is not running).
NOTE:
Check the MIL circuit if MIL does not illuminate. Refer to EC-
517, "Diagnosis Procedure".
2. When the engine is started, the MIL should go off.
NOTE:
If MIL continues to illuminate/blink, perform self-diagnoses and
inspect/repair accordingly because an emission-rela ted ECU has detected a malfunction in the emission
control systems components and/or the powertrain cont rol components (which affect vehicle emissions).
On Board Diagnosis FunctionINFOID:0000000009462119
ON BOARD DIAGNOSIS ITEM
The on board diagnostic system has the following functions.
BULB CHECK MODE
Description
This function allows damage inspection in the MIL bulb (blown, open circuit, etc.).
Operation Procedure
1. Turn ignition switch ON.
2. The MIL on the instrument panel should stay ON. If it remains OFF, check MIL circuit. Refer to EC-517, "Diagnosis Procedure"
.
SRT STATUS MODE
Description
This function allows to read if ECM has completed t he self-diagnoses of major emission control systems and
components. For SRT, refer to EC-72, "DIAGNOSIS DESCRIPTION : System Readiness Test (SRT) Code"
.
Operation Procedure
1. Turn ignition switch ON and wait 20 seconds.
2. SRT status is indicated as shown blow. • ECM continues to illuminate MIL if all SRT codes are set.
JSBIA1315ZZ
Diagnostic test mode Function
Bulb check MIL can be checked.
SRT status ECM can read if SRT codes are set.
Malfunction warning If ECM detects a malfunction, it illuminates or blinks MIL to inform the driver that a malfunction has been detected.
Self-diagnostic results DTCs or 1st trip DTCs stored in ECM can be read.
Accelerator pedal released po-
sition learning ECM can learn the accelerator pedal released position. Refer to
EC-177, "Work Procedure"
.
Throttle valve closed position
learning ECM can learn the throttle valve closed position. Refer to
EC-178, "Work Procedure"
.
Idle air volume learning ECM can learn the idle air volume. Refer to EC-179, "Work Procedure"
.
Mixture ratio self -learning value
clear Mixture ratio self-learning value can be erased. Refer to
EC-181, "Work Procedure"
.
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DIAGNOSIS SYSTEM (ECM)EC-75
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• ECM blinks MIL for about 10 seconds if all SRT codes are not set.
MALFUNCTION WARNING MODE
Description
In this function ECM turns on or blinks MIL when it detects a malfunction in the emission control system com-
ponents and/or the powertrain control components (which affe ct vehicle emissions) to inform the driver that a
malfunction has been detected.
Operation Procedure
1. Turn ignition switch ON.
2. Check that MIL illuminates. If it remains OFF, check MIL circuit. Refer to EC-517, "Diagnosis Procedure"
.
3. Start engine and let it idle. • For two trip detection logic diagnoses, ECM turns on MIL when it detects the same malfunction twice in
the two consecutive driving cycles.
• For 1st trip detection logic diagnoses, ECM turns on MIL when it detects a malfunction in one driving cycle.
• ECM blinks MIL when it detects a malfunction t hat may damage the three way catalyst (misfire).
SELF-DIAGNOSTIC RESULTS MODE
Description
This function allows to indicate DTCs or 1st trip DTCs stored in ECM according to the number of times MIL is
blinking.
How to Set Self-diagnostic Results Mode
NOTE:
• It is better to count the time accurately with a clock.
• It is impossible to switch the diagnostic mode when an accelerator pedal position sensor circuit has a mal-
function.
• After ignition switch is turned off, ECM is a lways released from the “self-diagnostic results” mode.
1. Confirm that accelerator pedal is fully releas ed, turn ignition switch ON and wait 3 seconds.
2. Repeat the following procedure quick ly five times within 5 seconds.
• Fully depress the accelerator pedal.
• Fully release the accelerator pedal.
3. Wait 7 seconds, fully depress the accelerator pedal and keep it depressed for approx. 10 seconds until the
MIL starts blinking.
NOTE:
Do not release the accelerator pedal for 10 seconds if MIL starts blinking during this period. This blinking
is displaying SRT status and is continued for another 10 seconds.
4. Fully release the accelerator pedal. ECM has entered to “Self-diagnostic results” mode.
JMBIA1515GB
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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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