EC-230
< DTC/CIRCUIT DIAGNOSIS >[QR25DE]
P0101 MAF SENSOR
Is the inspection result normal?
YES >> GO TO 7.
NO >> Replace MAF sensor (with intake air temperature sensor). Refer to EM-29, "Exploded View"
.
7.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR
Check the EVAP control system pressure sensor. Refer to EC-361, "Component Inspection"
.
Is the inspection result normal?
YES >> GO TO 8.
NO >> Replace EVAP control system pressure sensor. Refer to FL-18, "Removal and Installation"
.
8.CHECK MAF SENSOR
Check the MAF sensor. Refer to EC-230, "Component Inspection"
.
Is the inspection result normal?
YES >> Check intermittent incident. Refer to GI-43, "Intermittent Incident".
NO >> Replace MAF sensor. Refer to EM-29, "Exploded View"
.
Component InspectionINFOID:0000000009462180
1.CHECK MASS AIR FLOW SENSOR-1
With CONSULT
1. Turn ignition switch OFF.
2. Reconnect all harness connectors disconnected.
3. Start engine and warm it up to normal operating temperature.
4. Connect CONSULT and select “DATA MONITOR” mode of “ENGINE”.
5. Select “MAS A/F SE-B1” and check indication.
*: Check for linear voltage rise in response to engine being increased to about 4,000 rpm.
Is the inspection result normal?
YES >> INSPECTION END
NO >> GO TO 2.
2.CHECK FOR THE CAUSE OF UNEVEN AIR FL OW THROUGH MASS AIR FLOW SENSOR
1. Turn ignition switch OFF.
2. Check for the cause of uneven air flow through mass air flow sensor. Refer to the following.
- Crushed air ducts
- Malfunctioning seal of air cleaner element
- Uneven dirt of air cleaner element
- Intake valve deposits
- Improper specification of intake air system parts
Is the inspection result normal?
YES >> GO TO 4.
NO >> GO TO 3.
3.CHECK MASS AIR FLOW SENSOR-2
With CONSULT
1. Repair or replace malfunctioning part.
2. Start engine and warm it up to normal operating temperature.
3. Connect CONSULT and select “DATA MONITOR” mode of “ENGINE”.
4. Select “MAS A/F SE-B1” and check indication.
Monitor item Condition MAS A/F SE-B1
MAS A/F SE-B1 Ignition switch ON (Engine stopped.) Approx. 1.3 V
Idle (Engine is warmed-up to normal operating temper-
ature.) 1.3- 1.6 V
2,500 rpm (Engine is warmed-up to normal operating
temperature.) 1.8 - 2.2 V
Idle to about 4,000 rpm 1.3 - 1.6 V to Approx. 2.5 V*
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
EC-236
< DTC/CIRCUIT DIAGNOSIS >[QR25DE]
P010A MANIFOLD ABSOL
UTE PRESSURE SENSOR
P010A MANIFOLD ABSOLUTE PRESSURE SENSOR
DTC LogicINFOID:0000000009462184
DTC DETECTION LOGIC
NOTE:
If DTC P010A is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643.
Refer to EC-407, "DTC Logic"
.
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.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start engine and let it idle for 10 seconds.
2. Check DTC.
Is DTC detected?
YES >> Proceed to EC-236, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000009462185
1.CHECK MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR POWER SUPPLY CIRCUIT
1. Disconnect manifold absolute pressu re (MAP) sensor harness connector.
2. Turn ignition switch ON.
3. Check the voltage between MAP sensor harness connector and ground.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair or replace error-detected parts.
2.CHECK MAP SENSOR GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between manifold MAP sensor harness connector and ECM harness connector.
DTC No.CONSULT screen terms
(Trouble diagnosis content) DTC detecting condition Possible cause
P010A ABSL PRES SEN/CIRC
(Mass or volume air flow ″B ″ circuit) • An excessively low voltage from the
sensor is sent to ECM.
• An excessively high voltage from the sensor is sent to ECM. • Harness or connectors
(Manifold absolute pressure sen-
sor circuit is shorted.)
• Manifold absolute pressure sensor
+
-Voltag e
(Approx.)
MAP sensor
Connector Terminal F89 1 Ground 5 V
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
P010A MANIFOLD ABSOLUTE PRESSURE SENSOREC-237
< DTC/CIRCUIT DIAGNOSIS > [QR25DE]
C
D E
F
G H
I
J
K L
M A
EC
NP
O
4. Also check harness for short to power.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair or replace error-detected parts.
3.CHECK MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR INPUT SIGNAL CIRCUIT
1. Check the continuity between MAP sensor harness connector and ECM harness connector.
2. Also check harness for short to ground and to power.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair or replace error-detected parts.
4.CHECK MAP SENSOR
Refer to EC-237, "Component Inspection (MAP Sensor)"
.
Is the inspection result normal?
YES >> Check intermittent incident. Refer to GI-43, "Intermittent Incident".
NO >> Replace MAP sensor.
Component Inspection (MAP Sensor)INFOID:0000000009462186
1.CHECK MAP SENSOR-1
1. Turn ignition switch OFF.
2. Start engine and warm it up to normal operating temperature.
3. Turn ignition switch OFF, wait at least 5 seconds and then turn ON.
4. Check the voltage between ECM harness connector terminals as follows.
NOTE:
• To avoid the influence of intake manifold vacuum, check the voltage 1 or more minutes past after engine is stopped.
• Because the sensor is absolute pressure sens or, output value may differ depending on atmospheric
pressure and altitude.
5. Measure the atmospheric pressure.
NOTE:
As the atmospheric pressure described on the synoptic chart is the value at sea level, compensate the
pressure with the following chart.
+-
Continuity
MAP sensor ECM
Connector Terminal Connector Terminal F89 3 F90 58 Existed
+- Continuity
MAP sensor ECM
Connector Terminal Connector Terminal F89 2 F90 59 Existed
ECM
Connector + –
F90 Te r m i n a l
59 58
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
EC-238
< DTC/CIRCUIT DIAGNOSIS >[QR25DE]
P010A MANIFOLD ABSOL
UTE PRESSURE SENSOR
6. Check the manifold absolute pressure sensor value corresponding to the atmospheric pressure.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Replace MAP sensor.
2.CHECK MAP SENSOR-2
1. Start engine and let it idle.
2. Check intake manifold vacuum.
3. Check the voltage between ECM harness connector terminals as per the following.
4. Confirm the difference of the voltage when engine is stopped and at idling is within the values shown in
the following chart.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace MAP sensor.
Altitude (m) Compensated pressure (hPa)
00
200 -24
400 -47
600 -70
800 -92
1000 -114
1500 -168
2000 -218
Atmospheric pressure (hPa) Voltage (V)
800 3.1 – 3.7
850 3.3 – 3.9
900 3.5 – 4.1
950 3.8 – 4.3
1000 4.0 – 4.6
1050 4.2 – 4.8
JMBIA0870GB
ECM
Connector + –
F90 Te r m i n a l
59 58
Intake manifold vacuum [kPA (mmHg)] Voltage difference (V) -40 (-300) 1.5 – 2.0
-53.3 (-400) 2.0 – 2.6
-66.7 (-500) 2.6 – 3.2 -80 (-600) 3.2 – 3.8
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
EC-268
< DTC/CIRCUIT DIAGNOSIS >[QR25DE]
P0137 HO2S2
P0137 HO2S2
DTC LogicINFOID:0000000009462220
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 the various driving condition such as fuel-
cut.
DTC CONFIRMATION PROCEDURE
1.INSPECTION START
Do you have CONSULT?
Do you have CONSULT?
YES >> GO TO 2.
NO >> GO TO 5.
2.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:
For better results, perform “DTC WORK SU PPORT” at a temperature of 0 to 30°C (32 to 86 °F).
>> GO TO 3.
3.PERFORM DTC CONFIRMATION PROCEDURE
With CONSULT
1. Turn ignition switch ON and select “DATA MONITOR” mode of “ENGINE” using CONSULT.
2. Start engine and warm it up to 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. 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 70°C (158 °F).
7. Open engine hood.
8. Select “HO2S2 (B1) P1147” of “HO2S2” in “DTC WORK SUPPORT” mode of “ENGINE” using CONSULT.
9. Follow the instruction of CONSULT.
JPBIA5997ZZ
DTC No. CONSULT screen terms
(Trouble diagnosis content) DTC detecting condition Possible cause
P0137 HO2S2 (B1)
(O2 sensor circuit low voltage
bank 1 sensor 2) The maximum voltage from the heated oxygen
sensor 2 is not reached to the specified voltage. • Harness or connectors
(Heated oxygen sensor 2 circuit is
open or shorted)
• Heated oxygen sensor 2
• Fuel pressure
• Fuel injector
• Intake air leaks
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
EC-274
< DTC/CIRCUIT DIAGNOSIS >[QR25DE]
P0138 HO2S2
P0138 HO2S2
DTC LogicINFOID:0000000009462224
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 capa city of the three 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 the various driving con-
dition 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.
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.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION A
PBIB1848E
PBIB2376E
DTC No. CONSULT screen terms
(Trouble diagnosis content) DTC detecting condition Possible cause
P0138 HO2S2 (B1)
(O2 sensor circuit high voltage bank 1
sensor 2) A)
An excessively high voltage from
the sensor is sent to ECM. • Harness or connectors
(The sensor circuit is open or shorted)
• Heated oxygen sensor 2
B) The minimum voltage from the sen-
sor is not reached to the specified
voltage. • Harness or connectors
(The sensor circuit is open or shorted)
• Heated oxygen sensor 2
• Fuel pressure
• Fuel injector
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
EC-290
< DTC/CIRCUIT DIAGNOSIS >[QR25DE]
P014C, P014D, P015A,
P015B, A/F SENSOR 1
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-195, "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-195, "Component Function Check"
.
Is
“CMPLT” displayed on CONSULT screen?
YES >> GO TO 5.
NO >> Refer to EC-195, "Component Function Check"
.
5.PERFORM SELF-DIAGNOSIS
With CONSULT
Check the “SELF-DIAG RESULT”.
Is any DTC detected?
YES >> Proceed to EC-291, "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.
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.
Data monitor item Status
A/F SEN1 DIAG1 (B1) CMPLT
A/F SEN1 DIAG2 (B1)
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
EC-294
< DTC/CIRCUIT DIAGNOSIS >[QR25DE]
P0171 FUEL INJECTION SYSTEM FUNCTION
P0171 FUEL INJECTIO
N SYSTEM FUNCTION
DTC LogicINFOID:0000000009462234
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 the A/F sensors 1. The ECM calcu-
lates the necessary compensation to correct the of fset 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 lights up the MIL (2 trip detection logic).
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.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE-1
1. Clear the mixture ratio self-learning value. Refer to EC-181, "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-295, "Diagnosis Procedure".
NO >> Check exhaust and intake air leak visually.
4.PERFORM DTC CONFIRMATION PROCEDURE-2
1. Start engine and let it 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.CONSULT screen terms
(Trouble diagnosis content) DTC detecting condition Possible cause
P0171 FUEL SYS-LEAN-B1
(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 leaks
• A/F sensor 1
• Fuel injector
• Exhaust gas leaks
• Incorrect fuel pressure
• Lack of fuel
• Mass air flow sensor
• Incorrect PCV hose connection
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM