DTC Confirmation ProcedureNLEC1908CAUTION:
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 10 seconds
before conducting the next test.
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TESTING CONDITION:
+Always perform at a temperature above þ10ÉC (14ÉF).
+Never stop engine during this procedure. If the engine is
stopped, retry this procedure from step 2.
With CONSULT-II
NOTE:
The figure on the left will be displayed on the CONSULT-II
screen when you start the DTC Work Support. Ignore the first
figure and start the test.
ªCOMPLETEDº will be displayed on the screen as the second
figure when the test is completed properly.
1) Start engine and warm it up to normal operating temperature.
2) Turn ignition switch ªOFFº and wait at least 10 seconds.
3) Turn ignition switch ªONº and select ªHO2S2 (B1) P0139º of
ªHO2S2º in ªDTC WORK SUPPORTº mode with CONSULT-II.
4) Touch ªSTARTº.
5) Start engine and let it idle for at least 30 seconds.
6) Rev engine up to 2,000 rpm 2 or 3 times quickly under no load.
If ªCOMPLETEDº appears on CONSULT-II screen, go to step
10.
If ªCOMPLETEDº does not appear on CONSULT-II screen, go
to the following step.
7) Drive vehicle at a speed of more than 70 km/h (43 MPH) for 2
consecutive minutes.
8) Additionally, ªCOMPLETEDº will be displayed on the CON-
SULT-II screen when the accelerator pedal is completely
released after the vehicle is driven for 60 seconds or more
under the following conditions.
(If will take approximately 5 seconds.)
ENG SPEED 1,400 - 3,300 rpm
Vehicle speed 68 - 130 km/h (42 - 81 MPH)
B/FUEL SCHDL 3.0 - 14.0 msec
Selector lever D position
NOTE:
+If ªCOMPLETEDº appears on the CONSULT-II screen, go
to step 10.
+If ªCOMPLETEDº does not appear on the CONSULT-II
screen, go to the following step.
9) Stop the vehicle and let it idle until ªCOMPLETEDº is displayed
on the CONSULT-II screen. (It will take 6 minutes at the most.)
NOTE:
If ªCOMPLETEDº is not displayed after 6 minutes, retry from
step 2.
DTC P0139 HEATED OXYGEN SENSOR 2 (REAR)
(RESPONSE MONITORING)
SR20DE
DTC Confirmation Procedure
EC-771
10) Make sure that ªOKº is displayed after touching ªSELF-DIAG
RESULTSº.
If ªNGº is displayed, refer to ªDiagnostic Procedureº, EC-775.
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Overall Function CheckNLEC1486Use this procedure to check the overall function of the rear heated
oxygen sensor circuit. During this check, a 1st trip DTC might not
be confirmed.
With GST
1) Start engine and drive vehicle at a speed of more than 70 km/h
(43 MPH) for 2 consecutive minutes.
2) Stop vehicle with engine running.
3) Set voltmeter probes between ECM terminals 63 (HO2S2 sig-
nal) and engine ground.
4) Check the voltage when revving up to 4,000 rpm under no load
at least 10 times.
(Depress and release accelerator pedal as soon as possible.)
The voltage should change at more than 0.06V for 1 sec-
ond during this procedure.
If the voltage can be confirmed in step 4, step 5 is not
necessary.
5) Keep vehicle at idling for 10 minutes, then check the voltage.
Or check the voltage when coasting from 80 km/h (50 MPH)
in D position with ªSPORTS MODE SWº OFF.
The voltage should change at more than 0.06V for 1 sec-
ond during this procedure.
6) If NG, go to ªDiagnostic Procedureº, EC-775.
DTC P0139 HEATED OXYGEN SENSOR 2 (REAR)
(RESPONSE MONITORING)
SR20DE
DTC Confirmation Procedure (Cont'd)
EC-772
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.
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4. 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.
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4. Stop engine and reconnect mass air flow sensor harness connector.
5. Make sure 1st trip DTC P0100 is displayed.
6. Erase the 1st trip DTC memory. Refer to ªHow to Erase Emission-related Diagnostic Informationº, EC-594.
7. Make sure DTC P0000 is displayed.
8. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0172 detected? Is it difficult to start engine?
YesorNo
Ye s©Perform trouble diagnosis for DTC P0172. Refer to EC-800.
No©GO TO 3.
DTC P0139 HEATED OXYGEN SENSOR 2 (REAR)
(RESPONSE MONITORING)
SR20DE
Diagnostic Procedure (Cont'd)
EC-776
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Component InspectionNLEC1489HEATED OXYGEN SENSOR 2 (REAR)NLEC1489S01With CONSULT-II
1) Start engine and drive vehicle at a speed of more than 70 km/h
(43 MPH) for 2 consecutive minutes.
2) Stop vehicle with engine running.
3) Select ªFUEL INJECTIONº in ªACTIVE TESTº mode, and
select ªHO2S2 (B1)º as the monitor item with CONSULT-II.
4) Check ªHO2S2 (B1)º at idle speed when adjusting ªFUEL
INJECTIONº to±25%.
ªHO2S2 (B1)º should be above 0.68V at least once when
the ªFUEL INJECTIONº is +25%.
ªHO2S2 (B1)º should be below 0.45V at least once when
the ªFUEL INJECTIONº is þ25%.
CAUTION:
+Discard any heated oxygen sensor which has been
dropped from a height of more than 0.5 m (19.7 in) onto a
hard surface such as a concrete floor; use a new one.
+Before installing new oxygen sensor, clean exhaust sys-
tem threads using Oxygen Sensor Thread Cleaner tool
and approved anti-seize lubricant.
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Without CONSULT-II
1) Start engine and drive vehicle at a speed of more than 70 km/h
(43 MPH) for 2 consecutive minutes.
2) Stop vehicle with engine running.
3) Set voltmeter probes between ECM terminals 63 (HO2S2 sig-
nal) and engine ground.
4) Check the voltage when revving up to 4,000 rpm under no load
at least 10 times.
(Depress and release accelerator pedal as soon as possible.)
The voltage should be above 0.68V at least once.
If the voltage is above 0.68V at step 4, step 5 is not nec-
essary.
5) Keep vehicle at idling for 10 minutes, then check the voltage.
Or check the voltage when coasting from 80 km/h (50 MPH)
in D position with ªSPORTS MODE SWº OFF.
The voltage should be below 0.45V at least once.
CAUTION:
+Discard any heated oxygen sensor which has been
dropped from a height of more than 0.5 m (19.7 in) onto a
hard surface such as a concrete floor; use a new one.
+Before installing new oxygen sensor, clean exhaust sys-
tem threads using Oxygen Sensor Thread Cleaner tool
and approved anti-seize lubricant.
DTC P0139 HEATED OXYGEN SENSOR 2 (REAR)
(RESPONSE MONITORING)
SR20DE
Component Inspection
EC-778
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DTC Confirmation ProcedureNLEC1494NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch ªOFFº and wait at least 10 seconds
before conducting the next test.
With CONSULT-II
1) Turn ignition switch ªONº and select ªDATA MONITORº mode
with CONSULT-II.
2) Start engine and drive vehicle at a speed of more than 70 km/h
(43 MPH) for 2 consecutive minutes.
3) Stop vehicle with engine running.
4) Let engine idle for 1 minute.
5) Maintain the following conditions for at least 5 consecutive
seconds.
ENG SPEED 1,400 - 3,300 rpm
VHCL SPEED SE 68 - 130 km/h (48 - 81 MPH)
B/FUEL SCHDL 3.0 - 14.0 msec
COOLAN TEMP/S More than 70ÉC (158ÉF)
Selector lever Suitable position
6) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-783.
SEF032X
Overall Function CheckNLEC1495Use this procedure to check the overall function of the heated oxy-
gen sensor 2 (rear) circuit. During this check, a 1st trip DTC might
not be confirmed.
With GST
1) Start engine and drive vehicle at a speed of more than 70 km/h
(43 MPH) for 2 consecutive minutes.
2) Stop vehicle with engine running.
3) Set voltmeter probes between ECM terminals 63 (HO2S2 sig-
nal) and engine ground.
4) Check the voltage after revving up to 4,000 rpm under no load
at least 10 times.
(Depress and release accelerator pedal as soon as possible.)
The voltage should be below 2V during this procedure.
5) If NG, go to ªDiagnostic Procedureº, EC-783.
DTC P0140 HEATED OXYGEN SENSOR 2 (REAR)
(HIGH VOLTAGE)
SR20DE
DTC Confirmation Procedure
EC-780
4 DETECT MALFUNCTIONING PART
Check the following.
+Joint connector-2 (where fitted)
+Joint connector F46 (where fitted)
+Harness for open or short between heated oxygen sensor 2 (rear) and ECM.
©Repair open circuit or short to power in harness or connectors.
5 CHECK HARNESS CONNECTOR
Check heated oxygen sensor 2 (rear) harness connector for water.
Water should not exist.
OK or NG
OK©GO TO 6.
NG©Repair or replace harness connector.
6 CHECK HEATED OXYGEN SENSOR 2 (REAR)
Refer to ªComponent Inspectionº, EC-784.
OK or NG
OK©GO TO 7.
NG©Replace heated oxygen sensor 2 (rear).
7 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-670.
©INSPECTION END
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Component InspectionNLEC1498HEATED OXYGEN SENSOR 2 (REAR)NLEC1498S01With CONSULT-II
1) Start engine and drive vehicle at a speed of more than 70 km/h
(43 MPH) for 2 consecutive minutes.
2) Stop vehicle with engine running.
3) Select ªFUEL INJECTIONº in ªACTIVE TESTº mode, and
select ªHO2S2 (B1)º as the monitor item with CONSULT-II.
4) Check ªHO2S2 (B1)º at idle speed when adjusting ªFUEL
INJECTIONº to±25%.
ªHO2S2 (B1)º should be above 0.68V at least once when
the ªFUEL INJECTIONº is +25%.
ªHO2S2 (B1)º should be below 0.45V at least once when
the ªFUEL INJECTIONº is þ25%.
CAUTION:
+Discard any heated oxygen sensor which has been
dropped from a height of more than 0.5 m (19.7 in) onto a
hard surface such as a concrete floor; use a new one.
+Before installing new oxygen sensor, clean exhaust sys-
tem threads using Oxygen Sensor Thread Cleaner tool
and approved anti-seize lubricant.
DTC P0140 HEATED OXYGEN SENSOR 2 (REAR)
(HIGH VOLTAGE)
SR20DE
Diagnostic Procedure (Cont'd)
EC-784
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SEF032X
Without CONSULT-II
1) Start engine and drive vehicle at a speed of more than 70 km/h
(43 MPH) for 2 consecutive minutes.
2) Stop vehicle with engine running.
3) Set voltmeter probes between ECM terminals 63 (HO2S2 sig-
nal) and engine ground.
4) Check the voltage when revving up to 4,000 rpm under no load
at least 10 times.
(Depress and release accelerator pedal as soon as possible.)
The voltage should be above 0.68V at least once.
If the voltage is above 0.68V at step 4, step 5 is not nec-
essary.
5) Keep vehicle at idling for 10 minutes, then check the voltage.
Or check the voltage when coasting from 80 km/h (50 MPH)
in D position with ªSPORTS MODE SWº OFF.
The voltage should be below 0.45V at least once.
CAUTION:
+Discard any heated oxygen sensor which has been
dropped from a height of more than 0.5 m (19.7 in) onto a
hard surface such as a concrete floor; use a new one.
+Before installing new oxygen sensor, clean exhaust sys-
tem threads using Oxygen Sensor Thread Cleaner tool
and approved anti-seize lubricant.
DTC P0140 HEATED OXYGEN SENSOR 2 (REAR)
(HIGH VOLTAGE)
SR20DE
Component Inspection (Cont'd)
EC-785
On Board Diagnosis LogicNLEC1507With the Air/Fuel Mixture Ratio Self-Learning Control, the actual mixture ratio can be brought closely to the
theoretical mixture ratio based on the mixture ratio feedback signal from the heated oxygen sensor 1 (front).
The ECM calculates the necessary compensation to correct the offset between the actual and the theoretical
ratios.
In case the amount of the compensation value is extremely large (The actual mixture ratio is too lean.), the
ECM judges the condition as the fuel injection system malfunction and lights up the MIL (2 trip detection logic).
Sensor Input Signal to ECM ECM function Actuator
Heated oxygen sensor 1 (front)Density of oxygen in exhaust gas
(Mixture ratio feedback signal)Fuel injection & mixture
ratio controlInjectors
DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P0171+Fuel injection system does not operate properly.
+The amount of mixture ratio compensation is too large.
(The mixture ratio is too lean.)+Intake air leaks
+Heated oxygen sensor 1 (front)
+Injectors
+Exhaust gas leaks
+Incorrect fuel pressure
+Lack of fuel
+Mass air flow sensor
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DTC Confirmation ProcedureNLEC1508NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch ªOFFº and wait at least 10 seconds
before conducting the next test.
With CONSULT-II
1) Start engine and warm it up to normal operating temperature.
2) Turn ignition switch ªOFFº and wait at least 10 seconds.
3) Turn ignition switch ªONº and select ªSELF-LEARN CON-
TROLº in ªWORK SUPPORTº mode with CONSULT-II.
4) Clear the self-learning control coefficient by touching ªCLEARº.
5) Select ªDATA MONITORº mode with CONSULT-II.
6) Start engine again and let it idle for at least 10 minutes.
The 1st trip DTC P0171 should be detected at this stage, if a
malfunction exists. If so, go to ªDiagnostic Procedureº,
EC-796.
7) If it is difficult to start engine at step 6, the fuel injection sys-
tem has a malfunction.
8) Crank engine while depressing accelerator pedal. If engine
starts, go to ªDiagnostic Procedureº, EC-796. If engine does
not start, visually check for exhaust and intake air leak.
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With GST
1) Start engine and warm it up to normal operating temperature.
2) Turn ignition switch ªOFFº and wait at least 10 seconds.
3) Disconnect mass air flow sensor harness connector. Then
restart and run engine for at least 3 seconds at idle speed.
4) Stop engine and reconnect mass air flow sensor harness con-
nector.
5) Select ªMODE 7º with GST. Make sure 1st trip DTC P0100 is
detected.
6) Select ªMODE 4º with GST and erase the 1st trip DTC P0100.
DTC P0171 FUEL INJECTION SYSTEM FUNCTION
(LEAN SIDE)
SR20DE
On Board Diagnosis Logic
EC-792