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-78
< SYSTEM DESCRIPTION >[QR25DE]
DIAGNOSIS SYSTEM (ECM)
Freeze Frame Data and 1st Trip Freeze Frame Data
*: The items are the same as those of 1st trip freeze frame data.
DATA MONITOR MODE
NOTE:
• The following table includes information (items) inapplicable to this vehicle. For information (items) applica- ble to this vehicle, refer to CONSULT display items.
• For reference values of the following items, refer to EC-88, "Reference Value"
.
Monitored Item
Freeze frame data item* Description
DIAG TROUBLE CODE
[PXXXX] • The engine control compon
ent part/control system has a trouble code that is displayed as PXXXX. (Re-
fer to EC-105, "DTC Index"
.)
FUEL SYS-B1 • “Fuel injection system status” at the moment a malfunction is detected is displayed.
- One of the following mode is displayed.
- Mode2: Open loop due to detected system malfunction
- Mode3: Open loop due to driving conditions (power enrichment, deceleration enleanment)
- Mode4: Closed loop - using oxygen sensor(s) as feedback for fuel control
- Mode5: Open loop - has not yet satisfied condition to go to closed loop
CAL/LD VALUE [%] • The calculated load value at the moment a malfunction is detected is displayed.
COOLANT TEMP
[ ° C] or [ °F] • The engine coolant temperature at the moment a malfunction is detected is displayed.
L-FUEL TRM-B1 [%] • “Long-term fuel trim” at the moment a malfunction is detected is displayed.
• The long-term fuel trim indicates much more gradual feedback compensation to the base fuel schedule than short-term fuel trim.
S-FUEL TRM-B1 [%] • “Short-term fuel trim” at the moment a malfunction is detected is displayed.
• The short-term fuel trim indicates dynamic or instantaneous feedback compensation to the base fuel schedule.
ENGINE SPEED [rpm] • The engine speed at the moment a malfunction is detected is displayed.
VEHICL SPEED
[km/h] or [mph] • The vehicle speed at the moment a malfunction is detected is displayed.
ABSOL TH·P/S [%] • The throttle valve o pening angle at the moment a malfunction is detected is displayed.
B/FUEL SCHDL [msec] • The base fuel schedule at the moment a malfunction is detected is displayed.
INT/A TEMP SE
[ ° C] or [ °F] • The intake air temperature at the moment a malfunction is detected is displayed.
FUEL SYS-B2
• There items are displayed but are not applicable to this model.
L-FUEL TRM-B2 [%]
S-FUEL TRM-B2 [%]
INT MANI PRES [kPa]
COMBUST CONDITION
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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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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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ECM
EC-89
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CLSD THL POS
• Ignition switch: ON
(Engine stopped) Accelerator pedal: Fully released On
Accelerator pedal: Slightly depressed Off
AIR COND SIG • Engine: After warming up, idle the
engine Air conditioner switch: OFF Off
Air conditioner switch: ON
(Compressor operates.) On
PW/ST SIGNAL • Engine: After warming up, idle the
engine Steering wheel: Not being turned Off
Steering wheel: Being turned On
LOAD SIGNAL • Ignition switch: ON Rear window defogger switch: ON
and/or Lighting switch: 2nd position On
Rear window defogger switch and lighting
switch: OFF Off
IGNITION SW • Ignition switch: ON → OFF → ON On → Off → On
HEATER FAN SW • Engine: After warming up, idle the
engine Heater fan switch: ON On
Heater fan switch: OFF Off
BRAKE SW • Ignition switch: ON Brake pedal: Fully released Off
Brake pedal: Slightly depressed On
INJ PULSE-B1 • Engine: After warming up
• Selector lever: P or N
• Air conditioner switch: OFF
•No load Idle 2.0 - 3.0 msec
2,000 rpm 1.9 - 2.9 msec
IGN TIMING • Engine: After warming up
• Selector lever: P or N
• Air conditioner switch: OFF
•No load Idle 5
° - 15 ° BTDC
2,000 rpm 25 ° - 45 ° BTDC
CAL/LD VALUE • Engine: After warming up
• Selector lever: P or N
• Air conditioner switch: OFF
•No load Idle 10% - 35%
2,500 rpm 10% - 35%
MASS AIRFLOW • Engine: After warming up
• Selector lever: P or N
• Air conditioner switch: OFF
•No load Idle 1.0 - 4.0 g/s
2,500 rpm 4.0 - 10.0 g/s
PURG VOL C/V • Engine: After warming up
• Selector lever: P or N
• Air conditioner switch: OFF
•No load Idle
(Accelerator pedal: Not depressed even
slightly, after engine starting.) 0%
2,000 rpm 20% - 90%
INT/V TIM(B1) • Engine: After warming up
• Selector lever: P or N
• Air conditioner switch: OFF
•No load Idle
−5 ° - 5 °CA
4,000 rpm Approx. 0 ° - 30 °CA
EXH/V TIM B1 • Engine: After warming up
• Selector lever: P or N
• Air conditioner switch: OFF
•No load Idle
−5 ° - 5 °CA
2,000 rpm Approx. 0 ° - 40 °CA
INT/V SOL (B1) • Engine: Idle speed
• Selector lever: P or N
• Air conditioner switch: OFF
•No load After warming up 0%
Cold condition [Engine coolant tempera-
ture below 60 °C (140 °F)] Approx. 50% - 100%
SWRL CONT S/V • Ignition switch: ON
• Engine coolant temperature: Be- tween -12 °C (10 °F) and 59 °C
(138 °F) Accelerator pedal: Fully released On
Accelerator pedal: Fully depressed Off
Monitor Item Condition Values/Status
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EC-90
< ECU DIAGNOSIS INFORMATION >[QR25DE]
ECM
VIAS S/V-1• Engine: After warming up
• Selector lever: P or N
• Air conditioner switch: OFF
•No load When revving engine up to 5,000 rpm
quickly Off
→ On → Off
AIR COND RLY • Engine: After warming up, idle the
engine Air conditioner switch: OFF Off
Air conditioner switch: ON
(Compressor operates) On
FUEL PUMP RLY • For 1 second after turning ignition switch: ON
• Engine running or cranking On
• Except above Off
VENT CONT/V • Ignition switch: ON Off
THRTL RELAY • Ignition switch: ON On
COOLING FAN • Engine: After warming up, idle the
engine
• Air conditioner switch: OFF Engine coolant temperature is 97
°C
(207 °F) or less Off
Engine coolant temperature between
98 °C (208 °F) and 99 °C (210 °F) or more Low
Engine coolant temperature between
100 °C (212 °F) or more Hi
• Engine: After warming up, idle the engine
• Air conditioner switch: ON
• Refrigerant pressure is less than 1,280 kPa (12.80 bar, 13.05 kg/
cm
2, 185.6 psi) Engine coolant temperature is 97
°C
(207 °F) or less Off
Engine coolant temperature between
98 °C (208 °F) and 99 °C (210 °F) or more Mid
Engine coolant temperature between
100 °C (212 °F) or more Hi
HO2S2 HTR (B1) • Engine speed: 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
• Engine speed: Above 3,600 rpm Off
ALT DUTY SIG • Power generation voltage variable control: Operating On
• Power generation voltage variable control: Not operating Off
I/P PULLY SPD • Vehicle speed: More than 20 km/h (12 MPH) Almost the same speed as
the tachometer indication
VEHICLE SPEED • Turn drive wheels and compare CONSULT value with the speedometer indi-
cation. Almost the same speed as
the speedometer indication
IDL A/V LEARN • Engine: running Idle air volume learning has not been per-
formed yet. YET
Idle air volume learning has already been
performed successfully. CMPLT
TRVL AFTER MIL • Ignition switch: ON Vehicle has traveled after MIL has turned
ON. 0 - 65,535 km
(0 - 40,723 miles)
ENG OIL TEMP • Engine: After warming up More than 70 °C (158 °F)
A/F S1 HTR(B1) • Engine: After warming up, idle the engine
(More than 140 seconds after starting engine.) 4 - 100%
VHCL SPEED SE • Turn drive wheels and compare CONSULT value with the speedometer indi-
cation. Almost the same speed as
the speedometer indication
SET VHCL SPD • Engine: Running ASCD: Operating The preset vehicle speed is
displayed
MAIN SW • Ignition switch: ON MAIN switch: Pressed On
MAIN switch: Released Off
Monitor Item Condition Values/Status
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ECM
EC-91
< ECU DIAGNOSIS INFORMATION > [QR25DE]
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CANCEL SW • Ignition switch: ON
CANCEL switch: Pressed On
CANCEL switch: Released Off
RESUME/ACC SW • Ignition switch: ON RESUME/ACCELERATE switch:
Pressed On
RESUME/ACCELERATE switch: Re-
leased Off
SET SW • Ignition switch: ON SET/COAST switch: Pressed On
SET/COAST switch: Released Off
BRAKE SW1
(Brake pedal posi-
tion switch) • Ignition switch: ON Brake pedal: Fully released On
Brake pedal: Slightly depressed Off
BRAKE SW2
(Stop lamp switch) • Ignition switch: ON Brake pedal: Fully released Off
Brake pedal: Slightly depressed On
VHCL SPD CUT • Ignition switch: ON Non
LO SPEED CUT • Ignition switch: ON Non
AT OD MONITOR • Ignition switch: ON Off
AT OD CANCEL • Ignition switch: ON Off
CRUISE LAMP • Ignition switch: ON MAIN switch: Pressed at the 1st time
→
at the 2nd time On
→ Off
SET LAMP • MAIN switch: ON
• When vehicle speed: Between 40 km/h (25 MPH) and 144 km/h (89
MPH) ASCD: Operating On
ASCD: Not operating Off
ALT DUTY • Engine speed: Idle 0 - 80%
BAT CUR SEN • Engine speed: Idle
• Battery: Fully charged
*2
• Selector lever: P or N
• Air conditioner switch: OFF
•No load Approx. 2,600 - 3,500 mV
A/F ADJ-B1 • Engine: running –0.330 - 0.330
TUMBLE POS SEN • Ignition switch: ON
• Engine coolant temperature: Be-
tween -12 °C (10 °F) and 59 °C
(138 °F) Accelerator pedal: Fully released Less than 1.4 V
Accelerator pedal: Fully depressed More than 2.8 V
P/N POSI SW • Ignition switch: ON Selector lever: P or N On
Selector lever: Except above Off
INT/A TEMP SE • Ignition switch: ON Indicates intake air tempera-
ture
AC PRESS SEN • Engine speed: Idle
• Both A/C switch and blower fan switch: ON (Compressor operates) 1.0 - 4.0 V
VTC DTY EX B1 • Engine: After warming up
• Selector lever: P or N
• Air conditioner switch: OFF
•No load Idle 0 - 2%
2,000 rpm Approx. 0- 90%
EVAP LEAK DIAG • Ignition switch: ON Depending on condition of
EVAP leak diagnosis
EVAP DIAG READY • Ignition switch: ON Depending on ready condi-
tion of EVAP leak diagnosis
BAT TEMP SEN • Engine: After warming up, idle the engine
• Selector lever: P or N
• Air conditioner switch: OFF
•No load Indicates the temperature
around the battery.
Monitor Item Condition Values/Status
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ECM
EC-93
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Terminal No.
(Wire color) Description
ConditionVa l u e
(Approx.)
+ − Signal name Input/
Output
1
(G) 128
(GR) Throttle control motor
(Close) Output[Ignition switch: ON]
• Engine stopped
• Selector lever: D
• Accelerator pedal: Fully released 1.8 V
2
(R) 128
(GR) Throttle control motor
power supply Input [Ignition switch: ON]
Battery voltage
(11 - 14 V)
3
(BG) 128
(GR) Throttle control motor
(Open) Output[Ignition switch: ON]
• Engine stopped
• Selector lever: D
• Accelerator pedal: Fully depressed 3.2 V
4
(W) 8
(B) Knock sensor Input [Engine is running]
• Idle speed 2.5 V
5
(W) 128
(GR) Intake manifold tuning
valve motor (Close) Output[Ignition switch ON]
• Engine coolant temperature: more than -30 °C (-22 °F)
• Accelerator pedal: Depressed → ful-
ly released Battery voltage appears for about
1 second.
6
(L) 128
(GR) Intake manifold tuning
valve motor power supply Input [Ignition switch: ON]
Battery voltage
(11 - 14 V)
7
(B) 128
(GR) Intake manifold tuning
valve motor (Open) Output[Ignition switch ON]
• Engine coolant temperature: more
than -30 °C (-22 °F)
• Accelerator pedal: Fully released →
depressed Battery voltage appears for about
1 second.
8
(B) —Sensor ground
(Knock sensor) —— —
9
(Y) 10
(BR)
13
(BR) 14
(Y) 128
(GR) Fuel injector No. 4
Fuel injector No. 3
Fuel injector No. 1
Fuel injector No. 2 Output[Engine is running]
• Warm-up condition
• Idle speed NOTE:
The pulse cycle changes depending
on rpm at idle Battery voltage
(11 - 14 V)
[Engine is running]
• Warm-up condition
• Engine speed: 2,000 rpm Battery voltage
(11 - 14 V)
JMBIA0326GB
JMBIA0324GB
JMBIA0089GB
JMBIA0090GB
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