P0139, P0159 HO2S2EC-779
< DTC/CIRCUIT DIAGNOSIS > [VQ35DE]
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Will CONSULT be used?
YES >> GO TO 2.
NO >> GO TO 3.
2.CHECK HEATED OXYGEN SENSOR 2
With CONSULT
1. Turn ignition switch ON and select “DATA MONITOR” mode with CONSULT.
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 1 minute.
6. Select “FUEL INJECTION” in “A CTIVE TEST” mode, and select “HO2S2 (B1)/(B2)” as the monitor item
with CONSULT.
7. Check “HO2S2 (B1)/(B2)” at idle speed when adjusting “FUEL INJECTION” to ± 25%.
“HO2S2 (B1)/(B2)” should be above 0.68 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 >> Replace malfunctioning heated oxygen sensor 2. Refer to EM-152, "Removal and Installation
(LH)" or EM-153, "Removal and Installation (RH)".
3.CHECK HEATED OXYGEN SENSOR 2-I
Without CONSULT
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. Check the voltage between ECM harness connector terminals under the following conditions.
Is the inspection result normal?
YES >> INSPECTION END
NO >> GO TO 4.
4.CHECK HEATED OXYGEN SENSOR 2-II
Check the voltage between ECM harness connector terminals under the following conditions.
PBIB3458E
ECM
Condition Voltage
Connector +–
Terminal Terminal
F79 57
59Revving up to 4,000 rpm under no load at
least 10 times The voltage should be above 0.68 V at
least once during this procedure.
The voltage should be below 0.18 V at
least once during this procedure.
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Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
EC-780
< DTC/CIRCUIT DIAGNOSIS >[VQ35DE]
P0139, P0159 HO2S2
Is the inspection result normal?
YES >> INSPECTION END
NO >> GO TO 5.
5.CHECK HEATED OXYGEN SENSOR 2-III
Check the voltage between ECM harness connector terminals under the following conditions.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace malfunctioning heated oxygen sensor 2. Refer to EM-152, "Removal and Installation
(LH)" or EM-153, "Removal and Installation (RH)".
ECM
Condition Voltage
Connector +–
Terminal Terminal
F79 57
59 Keeping engine at idle for 10 minutes The voltage should be above 0.68 V at
least once during this procedure.
The voltage should be below 0.18 V at
least once during this procedure.
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ECM
Condition Voltage
Connector +–
Terminal Terminal
F79 57
59Coasting from 80 km/h (50 MPH) with se-
lector lever in the D position The voltage should be above 0.68 V at
least once during this procedure.
The voltage should be below 0.18 V at
least once during this procedure.
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Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
P014C, P014D, P014E, P014F, P015A, P015B, P015C, P015D A/F SENSOR 1
EC-781
< DTC/CIRCUIT DIAGNOSIS > [VQ35DE]
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P014C, P014D, P014E, P014F, P015A,
P015B, P015C, P015D A/F SENSOR
1
DTC LogicINFOID:0000000009462643
DTC DETECTION LOGIC
To judge malfunctions, 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 engi ne operating (speed and load), fuel feedback control con-
stant, and the A/F sensor 1 temperature index. Judgment is based on whether the compensated time (the A/F
signal cycling time index) is inordinately long or not.
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure
before conducting the next test.
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 more than 11 V at idle.
Do you have CONSULT?
YES >> GO TO 2.
NO >> GO TO 6.
2.PERFORM DTC CONFIRMATION PROCEDURE-1
With CONSULT
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. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1minute under no load.
6. Let engine idle for 1 minute.
7. Increase the engine speed up to about 3,600 rpm and keep it for 10 seconds.
8. Fully release accelerator pedal and then let engine idle for about 1 minute.
9. Check the items status of “DATA MONITOR” as follows.
NOTE:
If “PRSNT” changed to “ABSNT”, refer to EC-701, "Component Function Check"
.
DTC No. Trouble diagnosis name DTC detecting condition Possible Cause
P014C Air fuel ratio (A/F) sensor 1 (bank 1) circuit slow re-
sponse
• The response time of a A/F sensor 1 signal de-lays more than the specified time computed by
ECM. • Harness or connectors
(The A/F sensor 1 circuit is open or
shorted.)
• A/F sensor 1
P014D
P015A Air fuel ratio (A/F) sensor 1 (bank 1) circuit delayed re-
sponse
P015B
P014E Air fuel ratio (A/F) sensor 1 (bank 2) circuit slow re-
sponse
P014F
P015C Air fuel ratio (A/F) sensor 1 (bank 2) circuit delayed re-
sponse
P015D
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
EC-782
< DTC/CIRCUIT DIAGNOSIS >[VQ35DE]
P014C, P014D, P014E, P0
14F, P015A, P015B, P015C, P015D A/F SENSOR 1
Is “PRSNT” displayed on CONSULT screen?
YES >> GO TO 4.
NO >> GO TO 3.
3.PERFORM DTC CONFIRMATION PROCEDURE-2
With CONSULT
Perform DTC confirmation procedure-1 again.
Is
“PRSNT” displayed on CONSULT screen?
YES >> GO TO 4.
NO >> Refer to EC-701, "Component Function Check"
.
4.PERFORM DTC CONFIRMATION PROCEDURE-2
With CONSULT
1. Wait for about 20 seconds at idle.
2. Check the items status of “DATA MONITOR” as follows. NOTE:
If “CMPLT” changed to “INCMP”, refer to EC-701, "Component Function Check"
.
Is
“CMPLT” displayed on CONSULT screen?
YES >> GO TO 5.
NO >> Refer to EC-701, "Component Function Check"
.
5.PERFORM SELF-DIAGNOSIS
With CONSULT
Check the “SELF-DIAG RESULT”.
Is any DTC detected?
YES >> Proceed to EC-783, "Diagnosis Procedure".
NO >> INSPECTION END
6.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 fuel trim” and “Long term fuel trim” indications.
Is the total percentage within
±15%?
YES >> GO TO 8.
NO >> GO TO 7.
DTC Data monitor item Status
• P014C
• P014D
• P015A
• P015B A/F SEN1 DIAG3 (B1)
PRSNT
• P014E
• P014F
• P015C
• P015D A/F SEN1 DIAG3 (B2)
DTC Data monitor item Status
• P014C
• P014D
• P015A
• P015B A/F SEN1 DIAG1 (B1)
CMPLT
A/F SEN1 DIAG2 (B1)
• P014E
• P014F
• P015C
• P015D A/F SEN1 DIAG1 (B2)
A/F SEN1 DIAG2 (B2)
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
P014C, P014D, P014E, P014F, P015A, P015B, P015C, P015D A/F SENSOR 1
EC-783
< DTC/CIRCUIT DIAGNOSIS > [VQ35DE]
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7.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.
8.PERFORM DTC CONFIRMATION PROCEDURE
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. 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. Increase the engine speed up to about 3,600 rpm and keep it for 10 seconds.
7. Fully release accelerator pedal and then let engine idle for about 1 minute.
8. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Proceed to EC-783, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000009462644
1.RETIGHTEN A/F SENSOR 1
Loosen and retighten the A/F sensor 1. Refer to EM-152, "Removal and Installation (LH)"
or EM-153,
"Removal and Installation (RH)".
>> GO TO 2.
2.CHECK EXHAUST GAS LEAK
1. Start engine and run it at idle.
2. Listen for an exhaust gas leak before three way catalyst 1.
Is exhaust gas leak detected?
YES >> Repair or replace.
NO >> GO TO 3.
3.CHECK FOR INTAKE AIR LEAK
Listen for an intake air leak after the mass air flow sensor.
Is intake air leak detected?
YES >> Repair or replace.
NO >> GO TO 4.
PBIB1922E
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
EC-784
< DTC/CIRCUIT DIAGNOSIS >[VQ35DE]
P014C, P014D, P014E, P0
14F, P015A, P015B, P015C, P015D A/F SENSOR 1
4.CLEAR THE MIXTURE RATIO SELF-LEARNING VALUE
1. Clear the mixture ratio self-learning value. Refer to EC-685, "Work Procedure"
.
2. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171, P 0172, P0174 or P0175 detected? Is it difficult to start engine?
YES >> Perform trouble diagnosis for DTC P0171, P0174 or P0172, P0175. Refer to EC-787, "DTC Logic"
or EC-791, "DTC Logic".
NO >> GO TO 5.
5.CHECK AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY
1. Disconnect 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 7.
NO >> GO TO 6.
6.CHECK AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect IPDM E/R harness connector.
3. Check the continuity between A/F sensor 1 harness connector and IPDM E/R harness connector.
Is the inspection result normal?
YES >> Perform the trouble diagnosis for power supply circuit.
NO >> Repair or replace error-detected parts.
7.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.
DTCA/F sensor 1
Ground Voltage
Bank Connector Terminal
• P014C
• P014D
• P015A
• P015B 1F12 4
Ground Battery voltage
• P014E
• P014F
• P015C
• P015D 2F61 4
DTC
A/F sensor 1 IPDM E/R
Continuity
Bank Connector Terminal Connector Terminal
• P014C
• P014D
• P015A
• P015B 1F12 4
F8352
Existed
• P014E
• P014F
• P015C
• P015D 2F61 4 53
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
EC-786
< DTC/CIRCUIT DIAGNOSIS >[VQ35DE]
P014C, P014D, P014E, P0
14F, P015A, P015B, P015C, P015D A/F SENSOR 1
YES >> GO TO 11.
NO >> Repair or replace PCV valve. Refer to EC-548, "ENGINE CONTROL SYSTEM : Component Parts
Location".
11 .CHECK INTERMITTENT INCIDENT
Check intermittent incident. Refer to GI-43, "Intermittent Incident"
.
Is the inspection result normal?
YES >> Replace malfunctioning air fuel ratio (A/F) sensor 1. Refer to EM-152, "Removal and Installation
(LH)" or EM-153, "Removal and Installation (RH)".
NO >> Repair or replace error-detected parts.
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
P0171, P0174 FUEL INJECTION SYSTEM FUNCTION
EC-787
< DTC/CIRCUIT DIAGNOSIS > [VQ35DE]
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P0171, P0174 FUEL INJE
CTION SYSTEM FUNCTION
DTC LogicINFOID:0000000009462645
DTC DETECTION LOGIC
With 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 f eedback signal from A/F sensor 1. The ECM calculates
the necessary compensation to co rrect the offset between the actual and the theoretical ratios.
In case the amount of the compensation value is extrem ely large (the actual mixture ratio is too lean), the
ECM judges the condition as the fuel injection system malfunction and illuminates the MIL (2 trip detection
logic).
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conduc ted, always perform the following before conduct-
ing the next test.
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.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE-I
1. Clear the mixture ratio self-learning value. Refer to EC-685, "Work Procedure"
.
2. Start engine.
Is it difficult to start engine?
YES >> GO TO 3.
NO >> GO TO 4.
3.RESTART ENGINE
If it is difficult to start engine, the f uel injection system has a malfunction, too.
Crank engine while depressing accelerator pedal.
NOTE:
• When depressing accelerator pedal three-fourths (3/4 ) or more, the control system does not start the
engine. Do not depress accelerator pedal too much.
Does engine start?
YES >> Proceed to EC-788, "Diagnosis Procedure".
NO >> Check exhaust and intake air leakage visually.
4.PERFORM DTC CONFIRMATION PROCEDURE-II
1. Keep engine idle for at least 5 minutes.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
Sensor Input signal to ECM ECM function Actuator
A/F sensor 1 Density of oxygen in exhaust gas
(Mixture ratio feedback signal) Fuel injection control Fuel injector
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0171 Fuel injection system too
lean (bank 1)
• Fuel injection system does not operate properly.
• The amount of mixture ratio compensation is too
large. (The mixture ratio is too lean.) • Intake air leakage
• A/F sensor 1
• Fuel injector
• Exhaust gas leakage
• Incorrect fuel pressure
• Lack of fuel
• Mass air flow sensor
• Incorrect PCV hose connection
P0174
Fuel injection system too
lean (bank 2)
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM