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![INFINITI FX35 2004 Service Manual EC-244
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DTC P0138, P0158 HO2S2
Revision: 2004 November 2004 FX35/FX45
6. Check the voltage when revving up to 4,000 rpm under no load
at least 10 times.
(Depress and release accelerator pedal INFINITI FX35 2004 Service Manual EC-244
[VQ35DE]
DTC P0138, P0158 HO2S2
Revision: 2004 November 2004 FX35/FX45
6. Check the voltage when revving up to 4,000 rpm under no load
at least 10 times.
(Depress and release accelerator pedal](/manual-img/42/57021/w960_57021-1584.png)
EC-244
[VQ35DE]
DTC P0138, P0158 HO2S2
Revision: 2004 November 2004 FX35/FX45
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 0.63V at least once during this
procedure.
If the voltage is above 0.63V at step 6, step 7 is not neces-
sary.
7. Keep vehicle at 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.
The voltage should be below 0.48V 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 InstallationABS006OO
HEATED OXYGEN SENSOR 2
Refer to EM-26, "EXHAUST MANIFOLD AND THREE WAY CATALYST" .
PBIB1607E
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DTC P0139, P0159 HO2S2PFP:226A0
Component DescriptionABS006OP
The heated oxygen sensor 2, after INFINITI FX35 2004 Service Manual DTC P0139, P0159 HO2S2
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Component DescriptionABS006OP
The heated oxygen sensor 2, after](/manual-img/42/57021/w960_57021-1585.png)
DTC P0139, P0159 HO2S2
EC-245
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DTC P0139, P0159 HO2S2PFP:226A0
Component DescriptionABS006OP
The heated oxygen sensor 2, after three way catalyst 1, monitors the
oxygen level in the exhaust gas on each bank.
Even if switching characteristics of the heated oxygen sensor 1 are
shifted, the air-fuel ratio is controlled to stoichiometric, by the signal
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 ModeABS006OQ
Specification data are reference values.
On Board Diagnosis LogicABS006OR
The heated oxygen sensor 2 has a much longer switching time
between rich and lean than the heated oxygen sensor 1. The oxygen
storage capacity before the three way catalyst 1 causes the longer
switching time. To judge the malfunctions of heated oxygen sensor
2, ECM monitors whether the switching response of the sensor's
voltage is faster than specified during the various driving condition
such as fuel-cut.
SEF327R
MONITOR ITEM CONDITION SPECIFICATION
HO2S2 (B1)
HO2S2 (B2)
Warm-up condition
After keeping engine speed
between 3,500 and 4,000 rpm for
1 minute and at idle for 1 minute
under no load.Revving engine from idle to 3,000 rpm
quickly.0 - 0.3V ←→ Approx. 0.6 -
1.0V
HO2S2 MNTR (B1)
HO2S2 MNTR (B2)LEAN ←→ RICH
SEF302U
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0139
0139
(Bank 1)
Heated oxygen sensor
2 circuit slow responseIt takes more time for the sensor to respond
between rich and lean than the specified time.
Harness or connectors
(The sensor circuit is open or shorted)
Heated oxygen sensor 2
Fuel pressure
Fuel injector
Intake air leaks P0159
0159
(Bank 2)
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![INFINITI FX35 2004 Service Manual EC-246
[VQ35DE]
DTC P0139, P0159 HO2S2
Revision: 2004 November 2004 FX35/FX45
DTC Confirmation ProcedureABS006OS
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition INFINITI FX35 2004 Service Manual EC-246
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DTC P0139, P0159 HO2S2
Revision: 2004 November 2004 FX35/FX45
DTC Confirmation ProcedureABS006OS
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition](/manual-img/42/57021/w960_57021-1586.png)
EC-246
[VQ35DE]
DTC P0139, P0159 HO2S2
Revision: 2004 November 2004 FX35/FX45
DTC Confirmation ProcedureABS006OS
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 better 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. Select “HO2S2 (B1) P0139” or “HO2S2 (B2) P0159” of “HO2S2” in “DTC WORK SUPPORT” mode with
CONSULT-II.
8. Start engine and following the instruction of CONSULT-II.
9. Make sure that “OK” is displayed after touching “SELF-DIAG RESULTS”.
If “NG” is displayed, refer to EC-251, "
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 CheckABS006OT
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 for 1 minute.
5. Set voltmeter probes between ECM terminal 74 [HO2S2 (B1) signal] or 55 [HO2S2 (B2) signal] and
ground.
SEF174Y
PBIB0115E
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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.)
A change of voltage should be more than 0.06V for 1 sec-
ond 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 change of voltage should be more than 0.06V for 1 sec-
ond during this procedure.
8. If NG, go to EC-251, "
Diagnostic Procedure" .
PBIB1607E
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EC-248
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DTC P0139, P0159 HO2S2
Revision: 2004 November 2004 FX35/FX45
Wiring DiagramABS006OU
BANK 1
TBWM0292E
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Specification data are reference values and are measured between each terminal and ground.
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.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
74 LG/BHeated oxygen sensor 2
(bank 1)[Engine is running]
Warm-up condition
Revving engine from idle to 3,000 rpm
quickly after the following conditions are met
–After keeping the engine speed between
3,500 and 4,000 rpm for 1 minute and at idle
for 1 minute under no load0 - Approximately 1.0V
78 B/RSensor ground
(Heated oxygen sensor)[Engine is running]
Warm-up condition
Idle speedApproximately 0V
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EC-250
[VQ35DE]
DTC P0139, P0159 HO2S2
Revision: 2004 November 2004 FX35/FX45
BANK 2
TBWM0293E
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Specification data are reference values and are measured between each terminal and ground.
CAUTI INFINITI FX35 2004 Service Manual DTC P0139, P0159 HO2S2
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Specification data are reference values and are measured between each terminal and ground.
CAUTI](/manual-img/42/57021/w960_57021-1591.png)
DTC P0139, P0159 HO2S2
EC-251
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Specification data are reference values and are measured between each terminal and ground.
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.
Diagnostic ProcedureABS00CH3
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground three screws on the body. Refer to EC-141, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
55 W/RHeated oxygen sensor 2
(bank 2)[Engine is running]
Warm-up condition
Revving engine from idle to 3,000 rpm
quickly after the following conditions are met
–After keeping the engine speed between
3,500 and 4,000 rpm for 1 minute and at idle
for 1 minute under no load0 - Approximately 1.0V
78 B/RSensor ground
(Heated oxygen sensor)[Engine is running]
Warm-up condition
Idle speedApproximately 0V
PBIB2195E