Component InspectionNCEC0078ENGINE COOLANT TEMPERATURE SENSORNCEC0078S01Check resistance as shown in the figure.
Temperature ÉC (ÉF) Resistance kW
20 (68)2.1 - 2.9
50 (122)0.68 - 1.00
90 (194)0.236 - 0.260
If NG, replace engine coolant temperature sensor.
4 DETECT MALFUNCTIONING PART
Check the following.
IHarness for open or short between ECM and engine coolant temperature sensor
IHarness for open or short between engine coolant temperature sensor and TCM (Transmission control module)
©Repair open circuit or short to ground or short to power in harness or connectors.
5 CHECK ENGINE COOLANT TEMPERATURE SENSOR
Refer to ªComponent Inspectionº, EC-SR-136.
OK or NG
OK©GO TO 6.
NG©Replace engine coolant temperature sensor.
6 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-SR-114.
©INSPECTION END
SEF152P
SEF012P
DTC P0115 ENGINE COOLANT TEMPERATURE SENSOR
(ECTS) (CIRCUIT)SR20DE
Component Inspection
EC-136
Component DescriptionNCEC0079NOTE:
If DTC P0120 (0120) is displayed with DTC P0510 (0510), first perform trouble diagnosis for DTC P0510,
EC-SR-271.
The throttle position sensor responds to the accelerator pedal movement. This sensor is a kind of potentiom-
eter which transforms the throttle position into output voltage, and emits the voltage signal to the ECM. In
addition, the sensor detects the opening and closing speed of the throttle valve and feeds the voltage signal
to the ECM.
Idle position of the throttle valve is determined by the ECM receiving the signal from the throttle position sen-
sor. This sensor controls engine operation such as fuel cut. On the other hand, the ªWide open and closed
throttle position switchº, which is built into the throttle position sensor unit, is not used for engine control.
CONSULT-II Reference Value in Data Monitor
Mode
NCEC0080Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
THRTL POS SENIEngine is idling. Throttle valve: fully closed 0.35 - 0.65V
IIgnition switch: ON
(Engine stopped)Throttle valve: fully opened 3.5 - 4.5V
ABSOL TH×P/SIEngine: Idle the engine Throttle valve: fully closed 0.0É
IIgnition switch: ON
(Engine stopped)Throttle valve: fully opened Approx. 80É
YEC118A
DTC P0120 THROTTLE POSITION SENSORSR20DE
Component Description
EC-137
Component InspectionNCEC0086THROTTLE POSITION SENSORNCEC0086S01With CONSULT-II
1) Start engine and warm it up to normal operating temperature.
2) Stop engine (ignition switch OFF).
3) Turn ignition switch ON.
4) Select ªDATA MONITORº mode with CONSULT-II.
5) Check voltage of ªTHRTL POS SENº under the following con-
ditions.
NOTE:
Voltage measurement must be made with throttle position
sensor installed in vehicle.
Throttle valve conditions Voltage V
Completely closed0.35 - 0.65 (a)
Partially openBetween (a) and (b)
Completely open3.5 - 4.5 (b)
If NG, adjust throttle position sensor idle position. Refer to
ªBasic Inspectionº, EC-SR-84.
4 DETECT MALFUNCTIONING PART
Check the following.
IHarness for open or short between ECM and throttle position sensor
IHarness for open or short between throttle position sensor and TCM (Transmission control module)
©Repair open circuit or short to ground or short to power in harness or connectors.
5 CHECK INPUT SIGNAL CIRCUIT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 92 and throttle position sensor harness connector terminal 2.
Refer to wiring diagram.
Continuity should exist.
3. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 6.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
6 CHECK THROTTLE POSITION SENSOR
Refer to ªComponent Inspectionº, EC-SR-142.
OK or NG
OK©GO TO 7.
NG©Replace throttle position sensor. To adjust it, perform ªBasic Inspectionº, EC-SR-84.
7 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-SR-114.
©INSPECTION END
NEF069A
DTC P0120 THROTTLE POSITION SENSORSR20DE
Component Inspection
EC-142
Diagnostic ProcedureNCEC0109
1 RETIGHTEN HEATED OXYGEN SENSOR 1 (FRONT)
1. Turn ignition switch ªOFFº.
2. Loosen and retighten heated oxygen sensor 1 (front).
Tightening torque:
40-60N×m (4.1 - 6.1 kg-m, 30 - 44 ft-lb)
©GO TO 2.
2 CLEAR THE SELF-LEARNING DATA.
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select ªSELF-LEARN CONTROLº in ªWORK SUPPORTº mode with CONSULT-II.
3. Clear the self-learning control coefficient by touching ªCLEARº.
SEF652Y4. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171 detected? Is it difficult to start engine?
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch ªOFFº.
3. Disconnect mass air flow sensor harness connector, and restart and run engine for at least 3 seconds at idle speed.
SEF203X4. Stop engine and reconnect mass air flow sensor harness connector.
5. Make sure diagnostic trouble code No. 0100 is displayed in Diagnostic Test Mode II.
6. Erase the diagnostic test mode II (Self-diagnostic results) memory. Refer to ªHOW TO ERASE EMISSION-RELATED DIAGNOSTIC
INFORMATIONº, EC-SR-56.
7. Make sure diagnostic trouble code No. 0000 is displayed in Diagnostic Test Mode II.
8. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC 0171 detected? Is it difficult to start engine?
YesorNo
Ye s©Perform trouble diagnosis for DTC P0171. Refer to EC-SR-212.
No©GO TO 3.
Mass air flow sensor
harness connector
Air cleaner
DTC P0131 HEATED OXYGEN SENSOR 1
(FRONT) (LEAN SHIFT MONITORING)SR20DE
Diagnostic Procedure
EC-153
Diagnostic Procedure=NCEC0117
1 RETIGHTEN HEATED OXYGEN SENSOR 1 (FRONT)
1. Turn ignition switch ªOFFº.
2. Loosen and retighten heated oxygen sensor 1 (front).
Tightening torque:
40-60N×m (4.1 - 6.1 kg-m, 30 - 44 ft-lb)
©GO TO 2.
2 CLEAR THE SELF-LEARNING DATA
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select ªSELF-LEARN CONTROLº in ªWORK SUPPORTº mode with CONSULT-II.
3. Clear the self-learning control coefficient by touching ªCLEARº.
SEF652Y4. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0172 detected? Is it difficult to start engine?
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch ªOFFº.
3. Disconnect mass air flow sensor harness connector, and restart and run engine for at least 3 seconds at idle speed.
SEF203X4. Stop engine and reconnect mass air flow sensor harness connector.
5. Make sure diagnostic trouble code No. 0100 is displayed in Diagnostic Test Mode II.
6. Erase the diagnostic test mode II (Self-diagnostic results) memory. Refer to ªHOW TO ERASE EMISSION-RELATED DIAGNOSTIC
INFORMATIONº, EC-SR-56.
7. Make sure diagnostic trouble code No. 0000 is displayed in Diagnostic Test Mode II.
8. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC 0172 detected? Is it difficult to start engine?
YesorNo
Ye s©Perform trouble diagnosis for DTC P0172. Refer to EC-SR-218.
No©GO TO 3.
Mass air flow sensor
harness connector
Air cleaner
DTC P0132 HEATED OXYGEN SENSOR 1
(FRONT) (RICH SHIFT MONITORING)SR20DE
Diagnostic Procedure
EC-159
On Board Diagnosis LogicNCEC0122To judge the malfunction of heated oxygen sensor 1 (front), this
diagnosis measures response time of heated oxygen sensor 1
(front) signal. The time is compensated by engine operating (speed
and load), fuel feedback control constant, and heated oxygen sen-
sor 1 (front) temperature index. Judgment is based on whether the
compensated time (heated oxygen sensor 1 (front) cycling time
index) is inordinately long or not.
DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P0133
0133IThe response of the voltage signal from the sensor takes
more than the specified time.IHarness or connectors
(The sensor circuit is open or shorted.)
IHeated oxygen sensor 1 (front)
IHeated oxygen sensor 1 (front) heater
IFuel pressure
IInjectors
IIntake air leaks
IExhaust gas leaks
IPCV
IMass air flow sensor
DTC Confirmation ProcedureNCEC0123CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch ªOFFº and wait at least 9 seconds
before conducting the next test.
TESTING CONDITION:
IAlways perform at a temperature above þ10ÉC (14ÉF).
IBefore performing the following procedure, confirm that
battery voltage is more than 11V at idle.
With CONSULT-II
1) Start engine and warm it up to normal operating temperature.
2) Stop engine and wait at least 9 seconds.
3) Turn ignition switch ªONº and select ªHO2S1 (B1) P0133º of
ªHO2S1º in ªDTC WORK SUPPORTº mode with CONSULT-II.
4) Touch ªSTARTº.
5) Start engine and let it idle for at least 3.5 minutes.
NOTE:
Never raise engine speed above 3,200 rpm after this step. If
the engine speed limit is exceeded, return to step 5.
6) When the following conditions are met, ªTESTINGº will be dis-
played on the CONSULT-II screen. Maintain the conditions
continuously until ªTESTINGº changes to ªCOMPLETEDº. (It
will take approximately 20 seconds.)
SEF010V
SEF831Y
SEF832Y
SEF658Y
DTC P0133 HEATED OXYGEN SENSOR 1
(FRONT) (RESPONSE MONITORING)SR20DE
On Board Diagnosis Logic
EC-163
5 CLEAR THE SELF-LEARNING DATA
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select ªSELF-LEARN CONTROLº in ªWORK SUPPORTº mode with CONSULT-II.
3. Clear the self-learning control coefficient by touching ªCLEARº.
SEF652Y4. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171 or P0172 detected? Is it difficult to start engine?
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch ªOFFº.
3. Disconnect mass air flow sensor harness connector, and restart and run engine for at least 3 seconds at idle speed.
SEF203X4. Stop engine and reconnect mass air flow sensor harness connector.
5. Make sure diagnostic trouble code No. 0100 is displayed in Diagnostic Test Mode II.
6. Erase the diagnostic test mode II (Self-diagnostic results) memory. Refer to ªHOW TO ERASE EMISSION-RELATED DIAGNOSTIC
INFORMATIONº, EC-SR-56.
7. Make sure diagnostic trouble code No. 0000 is displayed in Diagnostic Test Mode II.
8. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC 0171 or 0172 detected? Is it difficult to start engine?
YesorNo
Ye s©Perform trouble diagnosis for DTC P0171, P0172. Refer to EC-SR-212, 218.
No©GO TO 6.
6 CHECK INPUT SIGNAL CIRCUIT
1. Disconnect heated oxygen sensor 1 (front) harness connector and ECM harness connector.
2. Check harness continuity between ECM terminal 62 and heated oxygen sensor 1 (front) harness connector terminal 2.
Continuity should exist.
3. Check harness continuity between ECM terminal 62 (or terminal 2) and ground.
Continuity should not exist.
4. Also check harness for short to power.
OK or NG
OK©GO TO 7.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
Mass air flow sensor
harness connector
Air cleaner
DTC P0133 HEATED OXYGEN SENSOR 1
(FRONT) (RESPONSE MONITORING)SR20DE
Diagnostic Procedure (Cont'd)
EC-167
DescriptionNCEC0136SYSTEM DESCRIPTIONNCEC0136S01
Sensor Input Signal to ECMECM func-
tionActuator
Camshaft position sensor Engine speedHeated oxy-
gen sensor
1 (front)
heater con-
trolHeated oxygen sensor 1 (front)
heater
The ECM performs ON/OFF control of the heated oxygen sensor 1 (front) heater corresponding to the engine
operating condition.
OPERATIONNCEC0136S02
Engine speed Heated oxygen sensor 1 (front) heater
Above 3,200 rpm OFF
More than 20 seconds after exceeding 3,200 rpm ON
CONSULT-II Reference Value in Data Monitor
Mode
NCEC0137Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
HO2S2 HTR (B1)IEngine speed: Below 3,200 rpm ON
IMore than 20 seconds after exceeding 3,200 rpm OFF
ECM Terminals and Reference ValueNCEC0138Specification data are reference values and are measured between each terminal and 48 (ECM ground).
TERMI-
NAL NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
4LHeated oxygen sensor 1
(front) heater[Engine is running]
IEngine speed is below 3,200 rpm.Approximately 0V
[Engine is running]
IMore than 20 seconds after exceeding
3,200 rpm.BATTERY VOLTAGE
(11 - 14V)
On Board Diagnosis LogicNCEC0139
DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P0135
0135IThe current amperage in the heated oxygen sensor 1
(front) heater circuit is out of the normal range.
(An improper voltage drop signal is sent to ECM through
the heated oxygen sensor 1 (front) heater.)IHarness or connectors
(The heated oxygen sensor 1 (front) heater cir-
cuit is open or shorted.)
IHeated oxygen sensor 1 (front) heater
DTC Confirmation ProcedureNCEC0140NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch ªOFFº and wait at least 9 seconds
before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that bat-
tery voltage is between 10.5V and 16V at idle.
DTC P0135 HEATED OXYGEN SENSOR 1 (FRONT) HEATERSR20DE
Description
EC-175