Fuel INFINITI QX56 2011 Factory Service Manual
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![INFINITI QX56 2011 Factory Service Manual
P0132, P0152 A/F SENSOR 1EC-235
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P0132, P0152 A/F SENSOR 1
DTC LogicINFOID:0000000006217809
DTC DETECTION LOGIC
To judge the malfunct](/img/42/57033/w960_57033-2258.png "INFINITI QX56 2011 Factory Service Manual
P0132, P0152 A/F SENSOR 1EC-235
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P0132, P0152 A/F SENSOR 1
DTC LogicINFOID:0000000006217809
DTC DETECTION LOGIC
To judge the malfunct")
P0132, P0152 A/F SENSOR 1EC-235
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P0132, P0152 A/F SENSOR 1
DTC LogicINFOID:0000000006217809
DTC DETECTION LOGIC
To judge the malfunction, the diagnosis checks that the
A/F signal computed by ECM from the A/F sensor 1
signal is not inordinately high.
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is 10.5 V or more at idle.
>> GO TO 2.
2.CHECK A/F SENSOR FUNCTION
WITH CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Select “A/F SEN1 (B1)” or “A/F SEN1 (B2) ” in “DATA MONITOR” mode with CONSULT-III.
3. Check “A/F SEN1 (B1)” or “A/F SEN1 (B2)” indication.
WITH GST
Follow the procedure “With CONSULT-III” above.
Is the indication constantly approx. 5 V?
YES >> Go to EC-236, "Diagnosis Procedure".
NO >> GO TO 3.
3.PERFORM DTC CONFIRMATION PROCEDURE
WITH CONSULT-III
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Restart engine.
5. Drive and accelerate vehicle to more than 40 km/h (25 MPH) within 20 seconds after restarting engine. CAUTION:
Always drive vehicle at a safe speed.
6. Maintain the following conditions for approximately 20 consecutive seconds.
NOTE:
Keep the accelerator pedal as steady as possible during cruising.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible Cause
P0132 A/F SENSOR1 (B1)
[Air fuel ratio (A/F) sensor 1
(bank 1) circuit high voltage]
The A/F signal computed by ECM from the
A/F sensor 1 signal is constantly approx. 5 V. Harness or connectors
(The A/F sensor 1 circuit is open or
shorted.)
A/F sensor 1
P0152 A/F SENSOR1 (B2)
[Air fuel ratio (A/F) sensor 1
(bank 2) circuit high voltage]
ENG SPEED 1,000 - 3,200 rpm
VHCL SPEED SE More than 40 km/h (25 mph)
B/FUEL SCHDL 1.5 - 9.0 msec
Selector lever Suitable position
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EC-236
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P0132, P0152 A/F SENSOR 1
If this procedure is not completed within 1 minute af ter restarting engine at step 1, return to step
1.
7. Check 1st trip DTC.
W](/img/42/57033/w960_57033-2259.png "INFINITI QX56 2011 Factory Service Manual
EC-236
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P0132, P0152 A/F SENSOR 1
If this procedure is not completed within 1 minute af ter restarting engine at step 1, return to step
1.
7. Check 1st trip DTC.
W")
EC-236
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P0132, P0152 A/F SENSOR 1
If this procedure is not completed within 1 minute af ter restarting engine at step 1, return to step
1.
7. Check 1st trip DTC.
WITH GST
Follow the procedure “With CONSULT-III” above.
Is 1st trip DTC detected?
YES >> Go to EC-236, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217810
1.CHECK AIR FUEL RATIO SENSOR 1 POWER SUPPLY CIRCUIT
1. Disconnect air fuel ratio (A/F) sensor 1 harness connector.
2. Turn ignition switch ON.
3. Check the voltage between A/F sensor 1 harness connector and ground.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
2.CHECK A/F SENSOR 1 INPUT SIGN AL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between A/F sensor 1 harness connector and ECM harness connector.
4. Check the continuity between A/F sensor 1 harness connector and ground, or ECM harness connector
and ground.
5. Also check harness for short to power.
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 A/F SENSOR 1 GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between A/F sensor 1 harness connector and ECM harness connector.
DTCA/F sensor 1
Ground Voltage
Bank Connector Terminal
P0130 1 F67 4 Ground 3.0 V
P0150 2 F68 4
DTC A/F sensor 1 ECM
Continuity
Bank Connector Terminal Connector Terminal
P0130 1 F67 3 F11088
Existed
P0150 2 F68 3 78
DTC A/F sensor 1 ECM
Ground Continuity
Bank Connector Terminal Connector Terminal
P0130 1 F67 3 F11088
Ground Not existed
P0150 2 F68 3 78
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EC-238
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P0133, P0153 A/F SENSOR 1
P0133, P0153 A/F SENSOR 1
DTC LogicINFOID:0000000006217811
DTC DETECTION LOGIC
To judge the malfunction of A/F sensor
1, this diagn](/img/42/57033/w960_57033-2261.png "INFINITI QX56 2011 Factory Service Manual
EC-238
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P0133, P0153 A/F SENSOR 1
P0133, P0153 A/F SENSOR 1
DTC LogicINFOID:0000000006217811
DTC DETECTION LOGIC
To judge the malfunction of A/F sensor
1, this diagn")
EC-238
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P0133, P0153 A/F SENSOR 1
P0133, P0153 A/F SENSOR 1
DTC LogicINFOID:0000000006217811
DTC DETECTION LOGIC
To judge the malfunction of A/F sensor
1, this diagnosis measures response time of the A/F signal computed
by ECM from the A/F sensor 1 signal. The time is compensated by engine operating (speed and load), fuel
feedback control constant, and the A/F sensor 1 temper ature index. Judgment is based on whether the com-
pensated time (the A/F signal cycling time index) is inordinately long or not.
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is 11 V or more at idle.
Will CONSULT-III be used?
YES >> GO TO 2.
NO >> GO TO 5.
2.PERFORM DTC CONFIRMATION PROCEDURE-I
WITH CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Restart engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
6. Let engine idle for 1 minute.
7. Select “A/F SEN1(B1) P1278/P1279” (for DTC P 0133) or “A/F SEN1(B2) P1288/P1289” (for DTC P0153)
of “A/F SEN1” in “DTC WORK SUPPORT” mode with CONSULT-III.
8. Touch “START”.
Is
“COMPLETED” displayed on CONSULT-III screen?
YES >> GO TO 3
NO >> GO TO 4.
3.PERFORM DTC CONFIRMATION PROCEDURE-II
Touch “SELF-DIAG RESULT”.
Which is displayed on CONSULT-III screen?
OK >> INSPECTION END
NG >> Go to EC-239, "
Diagnosis Procedure".
4.PERFORM DTC CONFIRMATION PROCEDURE-II
DTC No.Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible Cause
P0133 A/F SENSOR1 (B1)
[Air fuel ratio (A/F) sensor 1
(bank 1) circuit slow response]
The response of the A/F signal computed by ECM from A/F sensor 1 signal takes
more than the specified time. Harness or connectors
(The A/F sensor 1 circuit is open or
shorted.)
A/F sensor 1
A/F sensor 1 heater
Fuel pressure
Fuel injector
Intake air leaks
Exhaust gas leaks
PCV
Mass air flow sensor
P0153
A/F SENSOR1 (B2)
[Air fuel ratio (A/F) sensor 1
(bank 2) circuit slow response]
Revision: 2010 May2011 QX56
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P0133, P0153 A/F SENSOR 1EC-239
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1. After perform the following procedure, “TESTIN
G” will be displayed on the CONSULT-III screen](/img/42/57033/w960_57033-2262.png "INFINITI QX56 2011 Factory Service Manual
P0133, P0153 A/F SENSOR 1EC-239
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1. After perform the following procedure, “TESTIN
G” will be displayed on the CONSULT-III screen")
P0133, P0153 A/F SENSOR 1EC-239
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1. After perform the following procedure, “TESTIN
G” will be displayed on the CONSULT-III screen.
- Increase the engine speed up to between 4,000 and 5,000 rpm and maintain that speed for 10 seconds.
- Fully release accelerator pedal and then let engine idle for approximately 10 seconds. If “TESTING” is not displayed after 10 seconds, refer to EC-161, "
Component Function Check".
2. Wait for approximately 20 seconds at idle under t he condition that “TESTING” is displayed on the CON-
SULT-III screen.
3. Check that “TESTING” changes to “COMPLETED”. If “TESTING” changed to “OUT OF CONDITION”, refer to EC-161, "
Component Function Check".
4. Touch “SELF-DIAG RESULT”.
Which is displayed on CONSULT-III screen?
OK >> INSPECTION END
NG >> Go to EC-239, "
Diagnosis Procedure".
5.CHECK AIR-FUEL RATIO SELF-LEARNING VALUE
WITH GST
1. Start engine and warm it up to normal operating temperature.
2. Select Service $01 with GST.
3. Calculate the total value of “Short term f uel trim” and “Long term fuel trim” indications.
Is the total percentage within
±15%?
YES >> GO TO 7.
NO >> GO TO 6.
6.DETECT MALFUNCTIONING PART
Check the following.
Intake air leaks
Exhaust gas leaks
Incorrect fuel pressure
Lack of fuel
Fuel injector
Incorrect PCV hose connection
PCV valve
Mass air flow sensor
>> Repair or replace malfunctioning part.
7.PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
3. Let engine idle for 1 minute.
4. Increase the engine speed up to between 4,000 and 5,000 rpm and maintain that speed for 10 seconds.
5. Fully release accelerator pedal and then let engine idle for approximately 1 minute.
6. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-239, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217812
1.RETIGHTEN AIR FUEL RATIO SENSOR 1
Loosen and retighten the air fuel rati o (A/F) sensor 1. Refer to EM-40, "
Exploded View".
>> GO TO 2.
2.CHECK EXHAUST GAS LEAKAGE
1. Start engine and run it at idle.
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EC-240
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P0133, P0153 A/F SENSOR 1
2. Listen for an exhaust gas leakage before three way catalyst (manifold).
Is exhaust gas leakage detected?
YES >> Repair or replace](/img/42/57033/w960_57033-2263.png "INFINITI QX56 2011 Factory Service Manual
EC-240
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P0133, P0153 A/F SENSOR 1
2. Listen for an exhaust gas leakage before three way catalyst (manifold).
Is exhaust gas leakage detected?
YES >> Repair or replace")
EC-240
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P0133, P0153 A/F SENSOR 1
2. Listen for an exhaust gas leakage before three way catalyst (manifold).
Is exhaust gas leakage detected?
YES >> Repair or replace malfunctioning part.
NO >> GO TO 3.
3.CHECK FOR INTAKE AIR LEAKAGE
Listen for an intake air leakage after the mass air flow sensor.
Is intake air leakage detected?
YES >> Repair or replace malfunctioning part.
NO >> GO TO 4.
4.CLEAR THE MIXTURE RATIO SELF-LEARNING VALUE
1. Clear the mixture ratio self-learning value. Refer to EC-152, "
Work Procedure".
2. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171, P172, P0174 or P 0175 detected? Is it difficult to start engine?
YES >> Perform trouble diagnosis for DTC P0171, P0174 or P0172, P0175. Refer to EC-263, "DTC Logic"
or EC-267, "DTC Logic".
NO >> GO TO 5.
5.CHECK AIR FUEL RATIO SENSOR 1 POWER SUPPLY CIRCUIT
1. Disconnect air fuel ratio (A/F) sensor 1 harness connector.
2. Turn ignition switch ON.
3. Check the voltage between A/F sensor 1 harness connector and ground.
Is the inspection result normal?
YES >> GO TO 6.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
6.CHECK A/F SENSOR 1 INPUT SIGN AL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between A/F sensor 1 harness connector and ECM harness connector.
4. Check the continuity between A/F sensor 1 harness connector and ground, or ECM harness connector
and ground.
PBIB1216E
DTC A/F sensor 1
Ground Voltage
Bank Connector Terminal
P0133 1 F67 4 Ground 3.0 V
P0153 2 F68 4
DTC A/F sensor 1 ECM
Continuity
Bank Connector Terminal Connector Terminal
P0133 1 F67 3 F11088
Existed
P0153 2 F68 3 78
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P0137, P0157 HO2S2EC-243
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P0137, P0157 HO2S2
DTC LogicINFOID:0000000006217813
DTC DETECTION LOGIC
The heated oxygen sensor 2 has a mu](/img/42/57033/w960_57033-2266.png "INFINITI QX56 2011 Factory Service Manual
P0137, P0157 HO2S2EC-243
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P0137, P0157 HO2S2
DTC LogicINFOID:0000000006217813
DTC DETECTION LOGIC
The heated oxygen sensor 2 has a mu")
P0137, P0157 HO2S2EC-243
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P0137, P0157 HO2S2
DTC LogicINFOID:0000000006217813
DTC DETECTION LOGIC
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 of the three way catalyst (manifold) causes the
longer switching time. To judge the malfunctions of heated oxygen
sensor 2, ECM monitors whether the maximum voltage of the sensor
is sufficiently high during various driving conditions such as fuel cut.
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
Will CONSULT-III be used?
YES >> GO TO 2.
NO >> GO TO 4.
2.PERFORM DTC CONFIRMATION PROCEDURE
WITH CONSULT-III
TESTING CONDITION:
For better results, perform “DTC WORK SUPPORT” at a temperature of 0 to 30 °C (32 to 86 °F).
1. Start engine and warm it up to the normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Restart engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
6. Let engine idle for 1 minute.
7. Select “DATA MONITOR” mode with CONSULT-III.
8. Check that “COOLAN TEMP/S” indicates more than 70 °C (158 °F).
If not, warm up engine and go to next step w hen “COOLAN TEMP/S” indication reaches 70 °C (158 °F).
9. Open engine hood.
10. Select “HO2S2 (B1) P1147” (for DTC P0137) or “HO2S2 (B2) P1167” (for DTC P0157) of “HO2S2” in
“DTC WORK SUPPORT” mode with CONSULT-III.
11. Follow the instruction of CONSULT-III display.
NOTE:
It will take at most 10 minutes until “COMPLETED” is displayed.
12. Touch “SELF-DIAG RESULTS”.
JMBIA1572GB
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0137 HO2S2 (B1)
[Heated oxygen sensor 2
(bank 1) circuit low voltage]
The maximum voltage from the sensor does
not reach the specified voltage. Harness or connectors
(The heated oxygen sensor 2 circuit is
open or shorted)
Heated oxygen sensor 2
Fuel pressure
Fuel injector
Intake air leaks
P0157
HO2S2 (B2)
[Heated oxygen sensor 2
(bank 2) circuit low voltage]
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EC-246
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P0137, P0157 HO2S2
3. Also check harness for short to power.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair open circuit, short to ground or sh](/img/42/57033/w960_57033-2269.png "INFINITI QX56 2011 Factory Service Manual
EC-246
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P0137, P0157 HO2S2
3. Also check harness for short to power.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair open circuit, short to ground or sh")
EC-246
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0137, P0157 HO2S2
3. Also check harness for 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 HEATED OXYGEN SENSOR 2
Refer to EC-246, "
Component Inspection (HO2 sensor 2)".
Is the inspection result normal?
YES >> GO TO 6.
NO >> GO TO 5.
5.REPLACE HEATED OXYGEN SENSOR 2
Replace malfunctioning heated oxygen sensor 2. Refer to EM-40, "
Exploded View".
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 exh aust system threads using Oxygen Sensor Thread
Cleaner [commercial service tool (J-43897-18 or J-43897-12)] and approved anti-seize lubricant
(commercial service tool).
>> INSPECTION END
6.CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
>> INSPECTION END
Component Inspection (HO2 sensor 2)INFOID:0000000006217816
1.INSPECTION START
Will CONSULT-III be used?
Will CONSULT-III be used?
YES >> GO TO 2.
NO >> GO TO 3.
2.CHECK HEATED OXYGEN SENSOR 2
With CONSULT-III
1. Start engine and warm it up to the normal operating temperature.
2. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
3. Let engine idle for 1 minute.
4. Select “FUEL INJECTION” in “ACT IVE TEST” mode, and select “HO2S2 (B1)/(B2)” as the monitor item
with CONSULT-III.
5. Check “HO2S2 (B1)/(B2)” at idle speed when adjusting “FUEL INJECTION” to ±25%.
“HO2S2 (B1)/(B2)” should be above 0.74 V at least once when the “FUEL INJECTION” is +25%.
“HO2S2 (B1)/(B2)” should be below 0.18 V at least once when the “FUEL INJECTION” is −25%.
Is the inspection result normal?
YES >> INSPECTION END
JMBIA1573GB
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P0138, P0158 HO2S2EC-249
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P0138, P0158 HO2S2
DTC LogicINFOID:0000000006217817
DTC DETECTION LOGIC
The heated oxygen sensor 2 has a mu](/img/42/57033/w960_57033-2272.png "INFINITI QX56 2011 Factory Service Manual
P0138, P0158 HO2S2EC-249
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P0138, P0158 HO2S2
DTC LogicINFOID:0000000006217817
DTC DETECTION LOGIC
The heated oxygen sensor 2 has a mu")
P0138, P0158 HO2S2EC-249
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P0138, P0158 HO2S2
DTC LogicINFOID:0000000006217817
DTC DETECTION LOGIC
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 of the thr ee way catalyst (manifold) causes the longer switching
time.
MALFUNCTION A
To judge the malfunctions of heated oxygen sensor 2, ECM monitors
whether the voltage is unusually high during various driving condi-
tions 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 var-
ious driving conditions such as fuel cut.
DTC CONFIRMATION PROCEDURE
PBIB1848E
PBIB2376E
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0138 HO2S2 (B1)
[Heated oxygen sensor 2
(bank 1) circuit high voltage] A)
An excessively high voltage from the
sensor is sent to ECM. Harness or connectors
(The 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 voltage. Harness or connectors
(The heated oxygen sensor 2 circuit is
open or shorted)
Heated oxygen sensor 2
Fuel pressure
Fuel injector
P0158 HO2S2 (B2)
[Heated oxygen sensor 2
(bank 2) circuit high voltage] A)
An excessively high voltage from the
sensor is sent to ECM. Harness or connectors
(The 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 voltage. Harness or connectors
(The heated oxygen sensor 2 circuit is
open or shorted)
Heated oxygen sensor 2
Fuel pressure
Fuel injector
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EC-254
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P0138, P0158 HO2S2
11 .CHECK HEATED OXYGEN SENSOR 2
Refer to EC-254, "
Component Inspection (HO2 sensor 2)".
Is the inspection result normal?
YES >> GO TO 13](/img/42/57033/w960_57033-2277.png "INFINITI QX56 2011 Factory Service Manual
EC-254
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P0138, P0158 HO2S2
11 .CHECK HEATED OXYGEN SENSOR 2
Refer to EC-254, \"
Component Inspection (HO2 sensor 2)\".
Is the inspection result normal?
YES >> GO TO 13")
EC-254
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P0138, P0158 HO2S2
11 .CHECK HEATED OXYGEN SENSOR 2
Refer to EC-254, "
Component Inspection (HO2 sensor 2)".
Is the inspection result normal?
YES >> GO TO 13.
NO >> GO TO 12.
12.REPLACE HEATED OXYGEN SENSOR 2
Replace malfunctioning heated oxygen sensor 2. Refer to EM-40, "
Exploded View".
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 exh aust system threads using Oxygen Sensor Thread
Cleaner [commercial service tool (J-43897-18 or J-43897-12)] and approved anti-seize lubricant
(commercial service tool).
>> INSPECTION END
13.CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
>> INSPECTION END
Component Inspection (HO2 sensor 2)INFOID:0000000006217820
1.INSPECTION START
Will CONSULT-III be used?
Will CONSULT-III be used?
YES >> GO TO 2.
NO >> GO TO 3.
2.CHECK HEATED OXYGEN SENSOR 2
WITH CONSULT-III
1. Start engine and warm it up to the normal operating temperature.
2. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
3. Let engine idle for 1 minute.
4. Select “FUEL INJECTION” in “ACT IVE TEST” mode, and select “HO2S2 (B1)/(B2)” as the monitor item
with CONSULT-III.
5. Check “HO2S2 (B1)/(B2)” at idle speed when adjusting “FUEL INJECTION” to ±25%.
“HO2S2 (B1)/(B2)” should be above 0.74 V at least once when the “FUEL INJECTION” is +25%.
“HO2S2 (B1)/(B2)” should be below 0.18 V at least once when the “FUEL INJECTION” is −25%.
Is the inspection result normal?
YES >> INSPECTION END
NO >> GO TO 6.
3.CHECK HEATED OXYGEN SENSOR 2-I
WITHOUT CONSULT-III
1. Start engine and warm it up to the normal operating temperature.
JMBIA1573GB
Revision: 2010 May2011 QX56
Page 2281 of 5598
![INFINITI QX56 2011 Factory Service Manual
P0139, P0159 HO2S2EC-257
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DTC LogicINFOID:0000000006217821
DTC DETECTION LOGIC
The heated oxygen sensor 2 has a mu](/img/42/57033/w960_57033-2280.png "INFINITI QX56 2011 Factory Service Manual
P0139, P0159 HO2S2EC-257
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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The heated oxygen sensor 2 has a mu")
P0139, P0159 HO2S2EC-257
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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P0139, P0159 HO2S2
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DTC DETECTION LOGIC
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 of the three way catalyst (manifold) causes the
longer switching time. To judge the malfunctions of heated oxygen
sensor 2, ECM monitors whether the switching response of the sen-
sor's voltage is faster than specified during various driving conditions
such as fuel cut.
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
Will CONSULT-III be used?
YES >> GO TO 2.
NO >> GO TO 4.
2.PERFORM DTC CONFIRMATION PROCEDURE
WITH CONSULT-III
TESTING CONDITION:
For better results, perform “DTC WORK SUPPORT” at a temperature of 0 to 30 °C (32 to 86 °F).
1. Start engine and warm it up to the normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Restart engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
6. Let engine idle for 1 minute.
7. Select “DATA MONITOR” mode with CONSULT-III.
8. Check 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).
9. Open engine hood.
10. Select “HO2S2 (B1) P0139” or “HO2S2 (B2) P 0159” of “HO2S2” in “DTC WORK SUPPORT” mode with
CONSULT-III.
11. Start engine and follow the instruction of CONSULT-III display.
NOTE:
It will take at most 10 minutes until “COMPLETED” is displayed.
12. Touch “SELF-DIAG RESULTS”.
SEF302U
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0139 HO2S2 (B1)
[Heated oxygen sensor 2
(bank 1) circuit slow response] It takes more time for the sensor to respond
between rich and lean than the specified
time. Harness or connectors
(The heated oxygen sensor 2 circuit is
open or shorted)
Heated oxygen sensor 2
Fuel pressure
Fuel injector
Intake air leaks
P0159
HO2S2 (B2)
[Heated oxygen sensor 2
(bank 2) circuit slow response]
Revision: 2010 May2011 QX56