oxygen sensor NISSAN LATIO 2007 Service Owner's Guide

EC-248Revision: June 2006
DTC P0137 HO2S2
2007 Versa
DTC P0137 HO2S2PFP:226A0
Component DescriptionUBS00QFE
The heated oxygen sensor 2, after three way catalyst (manifold),
monitors the oxygen level in the exhaust gas.
Even if switching characteristics of the air fuel ratio (A/F) sensor 1
are shifted, the air/fuel ratio is controlled to stoichiometric, by the sig-
nal from the heated oxygen sensor 2.
This sensor is made of ceramic zirconia. The zirconia generates volt-
age from approximately 1V in richer conditions to 0V in leaner condi-
tions.
Under normal conditions the heated oxygen sensor 2 is not used for
engine control operation.
CONSULT-II Reference Value in Data Monitor ModeUBS00QFF
Specification data are reference values.
On Board Diagnosis LogicUBS00QFG
The heated oxygen sensor 2 has a much longer switching time
between rich and lean than the air fuel ratio (A/F) sensor 1. The oxy-
gen storage capacity before the three way catalyst (manifold) causes
the longer switching time. To judge the malfunctions of heated oxy-
gen sensor 2, ECM monitors whether the maximum voltage of the
sensor is sufficiently high during the various driving condition such
as fuel-cut.
SEF 3 27 R
MONITOR ITEM CONDITION SPECIFICATION
HO2S2 (B1)

Revving engine from idle to 3,000 rpm quickly after the follow-
ing 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 load0 - 0.3V ←→ Approx. 0.6 - 1.0V
HO2S2 MNTR (B1) LEAN ←→ RICH
SEF 2 59 VA
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0137
0137Heated oxygen sensor 2 cir-
cuit low voltageThe maximum voltage from the sensor is
not reached to the specified voltage.

Harness or connectors
(Heated oxygen sensor 2 circuit open or
shorted.)

Heated oxygen sensor 2

Fuel pressure

Fuel injector

Intake air leaks

DTC P0137 HO2S2
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DTC Confirmation ProcedureUBS00QFH
NOTE:
If DTC confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
WITH CONSULT-II
TESTING CONDITION:
For the best results, perform DTC WORK SUPPORT at a temperature of 0 to 30°C (32 to 86°F).
1. Turn ignition switch ON and select “DATA MONITOR” mode with
CONSULT-II.
2. Start engine and warm it up to the normal operating tempera-
ture.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and keep the engine speed between 3,500 and
4,000 rpm for at least 1 minute under no load.
5. Let engine idle for 1 minute.
6. Make sure that “COOLAN TEMP/S” indicates more than 70°C
(158°F).
If not, warm up engine and go to next step when “COOLAN
TEMP/S” indication reaches to 70°C (158°F).
7. Open engine hood.
8. Select “HO2S2 (B1) P1147” (for DTC P0137) of “HO2S2” in “DTC WORK SUPPORT” mode with CON-
SULT-II.
9. Start engine and following the instruction of CONSULT-II.
NOTE:
It will take at most 10 minutes until “COMPLETED” is displayed.
10. Make sure that “OK” is displayed after touching “SELF-DIAG RESULTS”.
If “NG” is displayed, refer to EC-253, "
Diagnostic Procedure" .
If “CAN NOT BE DIAGNOSED” is displayed, perform the following.
a. Turn ignition switch OFF and leave the vehicle in a cool place (soak the vehicle).
b. Return to step 1.
Overall Function CheckUBS00QFI
Use this procedure to check the overall function of the heated oxygen sensor 2 circuit. During this check, a 1st
trip DTC might not be confirmed.
WITH GST
1. Start engine and warm it up to the normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
4. Let engine idle 1 minute.
5. Set voltmeter probes between ECM terminal 50 (HO2S2 signal) and ground.
SEF 1 74 Y
PBIB2373E

EC-252Revision: June 2006
DTC P0137 HO2S2
2007 Versa
Specification data are reference values and are measured between each terminal and ground.
Pulse signal is measured by CONSULT-II.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.) TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
5GHeated oxygen sensor 2
heater[Engine is running]

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.Approximately 10V
[Ignition switch: ON]

Engine stopped
[Engine is running]

Engine speed: Above 3,600 rpm.BATTERY VOLTAGE
(11 - 14V)
50 W Heated oxygen sensor 2[Engine is running]

Revving engine from idle to 3,000 rpm
quickly 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.0 - Approximately 1.0V
59 OSensor ground
(Heated oxygen sensor 2)[Engine is running]

Warm-up condition

Idle speedApproximately 0V
PBIA8148J

EC-254Revision: June 2006
DTC P0137 HO2S2
2007 Versa
2. CLEAR THE SELF-LEARNING DATA
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select “SELF-LEARNING CONT” in “WORK SUPPORT” mode
with CONSULT-II.
3. Clear the self-learning control coefficient by touching “CLEAR”.
4. 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 OFF.
3. Disconnect mass air flow sensor (1) harness connector, and
restart and run engine for at least 5 seconds at idle speed.
4. Stop engine and reconnect mass air flow sensor harness con-
nector.
5. Make sure DTC P0102 is displayed.
6. Erase the DTC memory. Refer to EC-60, "
HOW TO ERASE
EMISSION-RELATED DIAGNOSTIC INFORMATION" .
7. Make sure DTC P0000 is displayed.
8. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171 detected?
Is it difficult to start engine?
Ye s o r N o
Yes >> Perform trouble diagnosis for DTC P0171. Refer to EC-276, "DTC P0171 FUEL INJECTION SYS-
TEM FUNCTION" .
No >> GO TO 3.
3. CHECK HO2S2 GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect heated oxygen sensor 2 harness connector (2).
– : Vehicle front
–Heated oxygen sensor 2 (1)
3. Disconnect ECM harness connector.
4. Check harness continuity between ECM terminal 59 and HO2S2
terminal 1.
Refer to Wiring Diagram.
5. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
SEF 2 15 Z
BBIA0701E
Continuity should exist.
BBIA0700E

DTC P0137 HO2S2
EC-255
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4. CHECK HO2S2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal 50 and HO2S2 terminal 4.
Refer to Wiring Diagram.
2. Check harness continuity between ECM terminal 50 or HO2S2 terminal 4 and ground.
Refer to Wiring Diagram.
3. Also check harness for short to power.
OK or NG
OK >> GO TO 5.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
5. CHECK HEATED OXYGEN SENSOR 2
Refer to EC-255, "
Component Inspection" .
OK or NG
OK >> GO TO 6.
NG >> Replace heated oxygen sensor 2.
6. CHECK INTERMITTENT INCIDENT
Refer to EC-143, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionUBS00QFL
HEATED OXYGEN SENSOR 2
With CONSULT-II
1. Start engine and warm it up to the normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
4. Let engine idle for 1 minute.
5. Select “FUEL INJECTION” in “ACTIVE TEST” mode, and select
“HO2S2 (B1)” as the monitor item with CONSULT-II.Continuity should exist.
Continuity should not exist.
PBIB1783E

EC-256Revision: June 2006
DTC P0137 HO2S2
2007 Versa
6. Check “HO2S2 (B1)” at idle speed when adjusting “FUEL INJECTION” to ±25%.
“HO2S2 (B1)” should be above 0.68V at least once when the “FUEL INJECTION” is +25%.
“HO2S2 (B1)” should be below 0.18V at least once when the “FUEL INJECTION” is −25%.
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 system threads using Oxygen Sensor
Thread Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.
Without CONSULT-II
1. Start engine and warm it up to the normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
4. Let engine idle for 1 minute.
5. Set voltmeter probes between ECM terminal 50 (HO2S2 signal) and ground.
6. 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 during this
procedure.
If the voltage is above 0.68V at step 6, step 7 is not neces-
sary.
7. Keep vehicle idling for 10 minutes, then check voltage. Or check
the voltage when coasting from 80 km/h (50 MPH) in D position
with OD OFF (A/T, CVT), D position (CVT) or 3rd gear position
(M/T).
The voltage should be below 0.18V at least once during this
procedure.
8. If NG, replace heated oxygen sensor 2.
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 system threads using Oxygen Sensor
Thread Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.
Removal and InstallationUBS00QFM
HEATED OXYGEN SENSOR 2
Refer to EM-21, "EXHAUST MANIFOLD" .
PBIB2534E
PBIB2996E

DTC P0138 HO2S2
EC-257
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DTC P0138 HO2S2PFP:226A0
Component DescriptionUBS00QFN
The heated oxygen sensor 2, after three way catalyst (manifold),
monitors the oxygen level in the exhaust gas.
Even if switching characteristics of the air fuel ratio (A/F) sensor 1
are shifted, the air/fuel ratio is controlled to stoichiometric, by the sig-
nal from the heated oxygen sensor 2.
This sensor is made of ceramic zirconia. The zirconia generates volt-
age from approximately 1V in richer conditions to 0V in leaner condi-
tions.
Under normal conditions the heated oxygen sensor 2 is not used for
engine control operation.
CONSULT-II Reference Value in Data Monitor ModeUBS00QFO
Specification data are reference values.
On Board Diagnosis LogicUBS00QFP
The heated oxygen sensor 2 has a much longer switching time between rich and lean than the air fuel ratio (A/
F) sensor 1. The oxygen storage capacity before the three way catalyst (manifold) causes the longer switching
time.
MALFUNCTION A
To judge the malfunctions of rear heated oxygen sensor 2, ECM
monitors whether the voltage is unusually high during the various
driving condition such as fuel-cut.
MALFUNCTION B
To judge the malfunctions of heated oxygen sensor 2, ECM monitors
whether the minimum voltage of sensor is sufficiently low during the
various driving condition such as fuel-cut.
SEF 3 27 R
MONITOR ITEM CONDITION SPECIFICATION
HO2S2 (B1)

Revving engine from idle to 3,000 rpm quickly after the follow-
ing 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 load0 - 0.3V ←→ Approx. 0.6 - 1.0V
HO2S2 MNTR (B1) LEAN ←→ RICH
PBIB2266E
PBIB2376E

EC-258Revision: June 2006
DTC P0138 HO2S2
2007 Versa
DTC Confirmation ProcedureUBS00QFQ
Perform PROCEDURE FOR MALFUNCION A first.
If DTC cannot be confirmed, perform PROCEDURE FOR MALFUNCTION B.
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
PROCEDURE FOR MALFUNCTION A
With CONSULT-II
1. Turn ignition switch ON and select “DATA MONITOR” mode with CONSULT-II.
2. Start engine and warm it up to the normal operating temperature.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and keep the engine speed between 3,500 and
4,000 rpm for at least 1 minute under no load.
5. Let engine idle for 2 minutes.
6. If 1st trip DTC is detected, go to EC-262, "
PROCEDURE FOR
MALFUNCTION A" .
With GST
Follow the procedure “With CONSULT-II” above.
PROCEDURE FOR MALFUNCTION B
With CONSULT-II
TESTING CONDITION:
For the best results, perform DTC WORK SUPPORT at a temperature of 0 to 30°C (32 to 86°F).
1. Turn ignition switch ON and select “DATA MONITOR ” mode
with CONSULT-II
2. Start engine and warm it up to the normal operating tempera-
ture.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and keep the engine speed between 3,500 and
4,000 rpm for at least 1 minute under no load.
5. Let engine idle for 1 minute.
6. Make sure that “COOLAN TEMP/S” indicates more than 70°C
(158°F).
If not, warm up engine and go to next step when “COOLAN
TEMP/S” indication reaches to 70°C (158°F).
7. Open engine hood.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0138
0138Heated oxygen sensor 2
circuit high voltageA)An excessively high voltage from the
sensor is sent to ECM.

Harness or connectors
(Heated oxygen sensor 2 circuit is open
or shorted.)

Heated oxygen sensor 2
B)The minimum voltage from the sensor
is not reached to the specified volt-
age.

Harness or connectors
(Heated oxygen sensor circuit is open or
shorted.)

Heated oxygen sensor 2

Fuel pressure

Fuel injector
SEF 1 74 Y
SEF 1 74 Y

DTC P0138 HO2S2
EC-259
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Revision: June 20062007 Versa
8. Select “HO2S2 (B1) P1146” (for DTC P0138) of “HO2S2” in “DTC WORK SUPPORT” mode with CON-
SULT-II.
9. Start engine and following the instruction of COSULT-II.
NOTE:
It will take at most 10 minutes until “COMPLETED” is displayed.
10. Make sure that “OK” is displayed after touching “SELF-DIAG RESULTS”.
If “NG” is displayed, refer to EC-263, "
PROCEDURE FOR MALFUNCTION B" .
If “CAN NOT BE DIAGNOSED” is displayed, perform the following.
a. Turn ignition switch OFF and leave the vehicle in a cool place (soak the vehicle).
b. Return to step 1.
Overall Function CheckUBS00QFR
PROCEDURE FOR MALFUNCTION B
Use this procedure to check the overall function of the heated oxygen sensor 2 circuit. During this check, a 1st
trip DTC might not be confirmed.
With GST
1. Start engine and warm it up to the normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
4. Let engine idle 1 minute.
5. Set voltmeter probes between ECM terminal 50 (HO2S2 signal) and ground.
6. 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 below 0.18V at least once during this
procedure.
If the voltage can be confirmed in step 6, step 7 is not nec-
essary.
7. 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 OD OFF (A/T, CVT) or 3rd gear position (M/T).
The voltage should be below 0.18V at least once during this
procedure.
8. If NG, go to EC-263, "
PROCEDURE FOR MALFUNCTION B" .
PBIB2372E
PBIB2996E

DTC P0138 HO2S2
EC-261
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Revision: June 20062007 Versa
Specification data are reference values and are measured between each terminal and ground.
Pulse signal is measured by CONSULT-II.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.) TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
5GHeated oxygen sensor 2
heater[Engine is running]

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.Approximately 10V
[Ignition switch: ON]

Engine stopped
[Engine is running]

Engine speed: Above 3,600 rpm.BATTERY VOLTAGE
(11 - 14V)
50 W Heated oxygen sensor 2[Engine is running]

Revving engine from idle to 3,000 rpm
quickly 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.0 - Approximately 1.0V
59 OSensor ground
(Heated oxygen sensor 2)[Engine is running]

Warm-up condition

Idle speedApproximately 0V
PBIA8148J