ON BOARD DIAGNOSTIC (OBD) SYSTEM
EC-117
< FUNCTION DIAGNOSIS >[VQ25DE, VQ35DE]
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COOLAN TEMP/S°C or °F The engine coolant temperature (determined by
the signal voltage of the engine coolant tempera-
ture sensor) is displayed. When the engine coolant temperature
sensor is open or short-circuited,
ECM enters fail-safe mode. The en-
gine coolant temperature determined
by the ECM is displayed.
A/F SEN1 (B1)
V The A/F signal computed from the input signal of
the air fuel ratio (A/F) sensor 1 is displayed.
A/F SEN1 (B2)
HO2S2 (B1)
V The signal voltage of the heated oxygen sensor 2
is displayed.
HO2S2 (B2)
HO2S2 MNTR(B1)
RICH/LEAN Display of heated oxygen sensor 2 signal:
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.
HO2S2 MNTR(B2)
VHCL SPEED SE km/h or mph The vehicle speed computed from the vehicle
speed signal sent from combination meter is dis-
played.
BATTERY VOLT V The power supply voltage of ECM is displayed.
ACCEL SEN 1
V The accelerator pedal position sensor signal volt-
age is displayed. ACCEL SEN 2 signal is converted by
ECM internally. Thus, it differs from
ECM terminal voltage signal. ACCEL SEN 2
TP SEN 1-B1
V The throttle position sensor signal voltage is dis-
played. TP SEN 2-B1 signal is converted by
ECM internally. Thus, it differs from
ECM terminal voltage signal. TP SEN 2-B1
INT/A TEMP SE°C or °F The intake air temperature (determined by the
signal voltage of the intake air temperature sen-
sor) is indicated.
START SIGNAL ON/OFF Indicates start signal status [ON/OFF] computed
by the ECM according to the signals of engine
speed and battery voltage. After starting the engine, [OFF] is dis-
played regardless of the starter sig-
nal.
CLSD THL POS ON/OFF Indicates idle position [ON/OFF] computed by
ECM according to the accelerator pedal position
sensor signal.
AIR COND SIG ON/OFF Indicates [ON/OFF] condition of the air condition-
er switch as determined by the air conditioner sig-
nal.
P/N POSI SW ON/OFF Indicates [ON/OFF] condition from the park/neu-
tral position (PNP) signal.
PW/ST SIGNAL ON/OFF [ON/OFF] condition of the power steering system
(determined by the signal voltage of the power
steering pressure sensor) is indicated.
LOAD SIGNAL ON/OFF 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 light-
ing switch are OFF.
IGNITION SW ON/OFF Indicates [ON/OFF] condition from ignition switch
signal.
HEATER FAN SW ON/OFF 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 sig-
nals. When the engine is stopped, a certain
computed value is indicated.
INJ PULSE-B2Monitored item Unit Description Remarks
EC-120
< FUNCTION DIAGNOSIS >[VQ25DE, VQ35DE]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
*: This item is not used on this vehicle.
NOTE:
Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.
ACTIVE TEST MODE
Test Item
SET LAMP ON/OFF Indicates [ON/OFF] condition of SET lamp deter-
mined by the ECM according to the input signals.
BAT CUR SEN mV The signal voltage of battery current sensor is
displayed.
ALT DUTY SIG ON/OFF The control condition of the power generation
voltage variable control (determined by ECM ac-
cording to the input signals) is indicated.
ON: Power generation voltage variable control is
active.
OFF: Power generation voltage variable control
is inactive.
A/F ADJ-B1
— Indicates the correction of factor stored in ECM.
The factor is calculated from the difference be-
tween the target air-fuel ratio stored in ECM and
the air-fuel ratio calculated from A/F sensor 1 sig-
nal. A/F ADJ-B2
ALT DUTY % Indicates the duty ratio of the power generation
command value. The ratio is calculated by ECM
based on the battery current sensor signal. Monitored item Unit Description Remarks
TEST ITEM CONDITION JUDGMENT CHECK ITEM (REMEDY)
FUEL INJEC-
TION Engine: Return to the original
non-standard condition
Change the amount of fuel injec-
tion using CONSULT-III.If malfunctioning symptom disap-
pears, see CHECK ITEM. Harness and connectors
Fuel injector
Air fuel ratio (A/F) sensor 1
IGNITION TIM-
ING Engine: Return to the original
non-standard condition
Timing light: Set
Retard the ignition timing using
CONSULT-III.If malfunctioning symptom disap-
pears, see CHECK ITEM. Perform Idle Air Volume Learning.
POWER BAL-
ANCE Engine: After warming up, idle the
engine.
A/C switch OFF
Selector lever: P or N
Cut off each injector signal one at
a time using CONSULT-III.Engine runs rough or dies. Harness and connectors
Compression
Fuel injector
Power transistor
Spark plug
Ignition coil
COOLING FAN*
1
Ignition switch: ON
Turn the cooling fan “HI”, “MID”,
“LOW” and “OFF” using CON-
SULT-III.Cooling fan moves and stops. Harness and connectors
Cooling fan motor
IPDM E/R
ENG COOLANT
TEMP Engine: Return to the original
non-standard condition
Change the engine coolant tem-
perature using CONSULT-III.If malfunctioning symptom disap-
pears, see CHECK ITEM. Harness and connectors
Engine coolant temperature sen-
sor
Fuel injector
FUEL PUMP RE-
LAY Ignition switch: ON (Engine
stopped)
Turn the fuel pump relay “ON”
and “OFF” using CONSULT-III
and listen to operating sound.Fuel pump relay makes the operat-
ing sound. Harness and connectors
Fuel pump relay
EC-124
< COMPONENT DIAGNOSIS >[VQ25DE, VQ35DE]
TROUBLE DIAGNOSIS - SPECIFICATION VALUE
COMPONENT DIAGNOSIS
TROUBLE DIAGNOSIS - SPECIFICATION VALUE
DescriptionINFOID:0000000003856505
The specification (SP) value indicates the tolerance of the value that is displayed in “SPEC” of “DATA MONI-
TOR” mode of CONSULT-III during normal operation of the Engine Control System. When the value in “SPEC”
in “DATA MONITOR” mode is NOT within the SP value, the Engine Control System may have one or more
malfunctions.
The SP value is used to detect malfunctions that may affect the Engine Control System, but will not illuminate
the MI.
The SP value will be displayed for the following three items:
B/FUEL SCHDL (The fuel injection pulse width programmed into ECM prior to any learned on board correc-
tion)
A/F ALPHA-B1/B2 (The mean value of air-fuel ratio feedback correction factor per cycle)
MAS A/F SE-B1 (The signal voltage of the mass air flow sensor)
Component Function CheckINFOID:0000000003856506
1.START
Check that all of the following conditions are satisfied.
Vehicle driven distance: More than 5,000 km (3,107 miles)
Barometric pressure: 98.3 - 104.3 kPa (0.983 - 1.043 bar, 1.003 - 1.064 kg/cm
2, 14.25 - 15.12 psi)
Atmospheric temperature: 20 - 30°C (68 - 86°F)
Engine coolant temperature: 75 - 95°C (167 - 203°F)
Transmission: Warmed-up
- After the engine is warmed up to normal operating temperature, drive vehicle until “FLUID TEMP SE” (CVT
fluid temperature sensor signal) indicates more than 60°C (140°F).
Electrical load: Not applied
- Rear window defogger switch, air conditioner switch, lighting switch are OFF. Steering wheel is straight
ahead.
Engine speed: Idle
>> GO TO 2.
2.PERFORM “SPEC” OF “DATA MONITOR” MODE
With CONSULT-III
NOTE:
Perform “SPEC” in “DATA MONITOR” mode in maximum scale display.
1. Perform “EC-11, "
BASIC INSPECTION : Special Repair Requirement".
2. Select “B/FUEL SCHDL”, “A/F ALPHA-B1”, “A/F ALPHA-B2” and “MAS A/F SE-B1” in “SPEC” of “DATA
MONITOR” mode with CONSULT-III.
3. Check that monitor items are within the SP value.
Is the measurement value within the SP value?
YES >> INSPECTION END
NO >> Go to EC-125, "
Diagnosis Procedure".
P0037, P0038, P0057, P0058 HO2S2 HEATER
EC-143
< COMPONENT DIAGNOSIS >[VQ25DE, VQ35DE]
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P0037, P0038, P0057, P0058 HO2S2 HEATER
DescriptionINFOID:0000000003856519
SYSTEM DESCRIPTION
The ECM performs ON/OFF control of the heated oxygen sensor 2 heater corresponding to the engine speed,
amount of intake air and engine coolant temperature.
OPERATION
DTC LogicINFOID:0000000003856520
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is between 10.5 V and 16 V at
idle.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
With CONSULT-III
Sensor Input signal to ECM ECM function Actuator
Camshaft position sensor (PHASE)
Crankshaft position sensor (POS)Engine speed
Heated oxygen sensor 2
heater controlHeated oxygen sensor 2 heater
Engine coolant temperature sensor Engine coolant temperature
Mass air flow sensor Amount of intake air
Engine speed Heated oxygen sensor 2 heater
Above 3,600 rpmOFF
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 loadON
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0037Heated oxygen sensor 2
heater (bank 1) control
circuit lowThe current amperage in the heated oxygen sensor
2 heater circuit is out of the normal range.
(An excessively low voltage signal is sent to ECM
through the heated oxygen sensor 2 heater.) Harness or connectors
(The heated oxygen sensor 2 heater
circuit is open or shorted.)
Heated oxygen sensor 2 heater
P0038Heated oxygen sensor 2
heater (bank 1) control
circuit highThe current amperage in the heated oxygen sensor
2 heater circuit is out of the normal range.
(An excessively high voltage signal is sent to ECM
through the heated oxygen sensor 2 heater.) Harness or connectors
(The heated oxygen sensor 2 heater
circuit is shorted.)
Heated oxygen sensor 2 heater
P0057Heated oxygen sensor 2
heater (bank 2) control
circuit lowThe current amperage in the heated oxygen sensor
2 heater circuit is out of the normal range.
(An excessively low voltage signal is sent to ECM
through the heated oxygen sensor 2 heater.) Harness or connectors
(The heated oxygen sensor 2 heater
circuit is open or shorted.)
Heated oxygen sensor 2 heater
P0058Heated oxygen sensor 2
heater (bank 2) control
circuit highThe current amperage in the heated oxygen sensor
2 heater circuit is out of the normal range.
(An excessively high voltage signal is sent to ECM
through the heated oxygen sensor 2 heater.) Harness or connectors
(The heated oxygen sensor 2 heater
circuit is shorted.)
Heated oxygen sensor 2 heater
P0117, P0118 ECT SENSOR
EC-157
< COMPONENT DIAGNOSIS >[VQ25DE, VQ35DE]
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P0117, P0118 ECT SENSOR
DescriptionINFOID:0000000003856544
The engine coolant temperature sensor is used to detect the engine
coolant temperature. The sensor modifies a voltage signal from the
ECM. The modified signal returns to the ECM as the engine coolant
temperature input. The sensor uses a thermistor which is sensitive to
the change in temperature. The electrical resistance of the ther-
mistor decreases as temperature increases.
*: These data are reference values and are measured between ECM terminals 46
(Engine coolant temperature sensor) and 52 (Sensor ground).
DTC LogicINFOID:0000000003856545
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON and wait at least 5 seconds.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-158, "Diagnosis Procedure".
NO >> INSPECTION END
SEF594K
Engine coolant temperature
[°C (°F)]Voltage* (V) Resistance (kΩ)
–10 (14) 4.4 7.0 - 11.4
20 (68) 3.5 2.1 - 2.9
50 (122) 2.2 0.68 - 1.00
90 (194) 0.9 0.236 - 0.260
SEF012P
DTC No.Trouble Diagnosis
NameDTC detecting condition Possible Cause
P0117Engine coolant tem-
perature sensor cir-
cuit low inputAn excessively low voltage from the sensor is
sent to ECM.
Harness or connectors
(The sensor circuit is open or shorted.)
Engine coolant temperature sensor
P0118Engine coolant tem-
perature sensor cir-
cuit high inputAn excessively high voltage from the sensor is
sent to ECM.
EC-158
< COMPONENT DIAGNOSIS >[VQ25DE, VQ35DE]
P0117, P0118 ECT SENSOR
Diagnosis Procedure
INFOID:0000000003856546
1.CHECK GROUND CONNECTION
1. Turn ignition switch OFF.
2. Check ground connection E38. Refer to Ground Inspection in GI-37, "
Circuit Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair or replace ground connection.
2.CHECK ECT SENSOR POWER SUPPLY CIRCUIT
1. Disconnect engine coolant temperature (ECT) sensor harness connector.
2. Turn ignition switch ON.
3. Check the voltage between ECT sensor harness connector and ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
3.CHECK ECT SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between ECT sensor harness connector and ECM harness connector.
4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
4.CHECK ENGINE COOLANT TEMPERATURE SENSOR
Refer to EC-158, "
Component Inspection".
Is the inspection result normal?
YES >> GO TO 5.
NO >> Replace engine coolant temperature sensor.
5.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "
Intermittent Incident".
>> INSPECTION END
Component InspectionINFOID:0000000003856547
1.CHECK ENGINE COOLANT TEMPERATURE SENSOR
1. Turn ignition switch OFF.
2. Disconnect engine coolant temperature sensor harness connector.
3. Remove engine coolant temperature sensor.
ECT sensor
Ground Voltage
Connector Terminal
F80 1 Ground Approx. 5 V
ECT sensor ECM
Continuity
Connector Terminal Connector Terminal
F80 2 F8 52 Existed
P0117, P0118 ECT SENSOR
EC-159
< COMPONENT DIAGNOSIS >[VQ25DE, VQ35DE]
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4. Check resistance between engine coolant temperature sensor
terminals as per the following.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace engine coolant temperature sensor.
Terminals Condition Resistance (kΩ)
1 and 2 Temperature [°C (°F)]20 (68) 2.1 - 2.9
50 (122) 0.68 - 1.00
90 (194) 0.236 - 0.260
JMBIA0080ZZ
P0171, P0174 FUEL INJECTION SYSTEM FUNCTION
EC-199
< COMPONENT DIAGNOSIS >[VQ25DE, VQ35DE]
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5.PERFORM DTC CONFIRMATION PROCEDURE-III
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Start engine and drive the vehicle under similar conditions to (1st trip) Freeze Frame Data for 10 minutes.
Refer to the table below.
Hold the accelerator pedal as steady as possible.
Similar conditions to (1st trip) Freeze Frame Data mean that the following conditions should be satisfied at
the same time.
3. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-199, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000003856593
1.CHECK EXHAUST GAS LEAK
1. Start engine and run it at idle.
2. Listen for an exhaust gas leak before three way catalyst (manifold).
Is exhaust gas leak detected?
YES >> Repair or replace malfunctioning part.
NO >> GO TO 2.
2.CHECK FOR INTAKE AIR LEAK
1. Listen for an intake air leak after the mass air flow sensor.
2. Check PCV hose connection.
Is intake air leak detected?
YES >> Repair or replace malfunctioning part.
NO >> GO TO 3.
3.CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect corresponding A/F sensor 1 harness connector.
3. Disconnect ECM harness connector.
4. Check the continuity between A/F sensor 1 harness connector and ECM harness connector.
Engine speed Engine speed in the freeze frame data ± 400 rpm
Vehicle speed Vehicle speed in the freeze frame data ± 10 km/h (6 MPH)
Engine coolant temperature (T) conditionWhen the freeze frame data shows lower than 70 °C (158 °F),
T should be lower than 70 °C (158 °F).
When the freeze frame data shows higher than or equal to 70 °C (158 °F),
T should be higher than or equal to 70 °C (158 °F).
PBIB1216E