2011 NISSAN LATIO check engine

EC-752
< SERVICE INFORMATION >[MR18DE]
DTC P014C, P014D A/F SENSOR 1
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.
6. Increase the engine speed up to 4,000 to 5,000 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-754, "Diagnosis Procedure".
NO >> INSPECTION END
Revision: May 2010 2011 Versa

EC-754
< SERVICE INFORMATION >[MR18DE]
DTC P014C, P014D A/F SENSOR 1
Do not use ECM ground terminals when measuring input/output voltage. Doi
ng so may result in dam-
age to the ECM's transistor. Use a ground ot her than ECM terminals, such as the ground.
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)
Diagnosis ProcedureINFOID:0000000006341913
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten engine screw on the body. Refer to EC-638, "
Ground Inspection".
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2.RETIGHTEN AIR FUEL RATIO (A/F) SENSOR 1
Loosen and retighten the air fuel ratio (A/F) sensor 1. Refer to EM-141, "
Removal and Installation".
>> GO TO 3.
3.CHECK EXHAUST GAS LEAK
1. Start engine and run it at idle.
TERMI- NAL
NO. WIRE
COLOR ITEM
CONDITION DATA (DC Voltage)
3 G A/F sensor 1 heater [Engine is running]
•
Warm-up condition
• Idle speed (More than 140 seconds after starting
engine) Approximately 2.9 - 8.8 V
49 W A/F sensor 1 [Engine is running]
•
Warm-up condition
• Engine speed: 2,000 rpm Approximately 1.8 V
Output voltage varies with air fuel
ratio.
53 B A/F sensor 1 [Ignition switch: ON] Approximately 2.2 V
PBIA8148J
:Vehicle front
1. Body ground E24 2. Engine ground F9 3. Engine ground F16
4. Body ground E15
BBIA0698E
Revision: May 2010 2011 Versa

DTC P014C, P014D A/F SENSOR 1EC-755
< SERVICE INFORMATION > [MR18DE]
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2. Listen for an exhaust gas leak before three way catalyst (manifold).
OK or NG
OK >> GO TO 4.
NG >> Repair or replace.
4.CHECK FOR INTAKE AIR LEAK
Listen for an intake air leak after the mass air flow sensor.
OK or NG
OK >> GO TO 5.
NG >> Repair or replace.
5.CLEAR THE SELF-LEARNING DATA
With CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Select “SELF-LEARNING CONT” in “W ORK SUPPORT” mode with CONSULT-III.
3. Clear the self-learning control coefficient by touching “CLEAR” or “START”.
4. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171 or P0172 detect ed? Is it difficult to start engine?
Without CONSULT-III
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-542, "
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 or P 0172 detected? Is it difficult to
start engine?
Ye s o r N o
Yes >> Perform trouble diagnosis for DTC P0171, P0172. Refer to EC-758 or EC-764.
No >> GO TO 6.
6.CHECK AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
PBIB1216E
BBIA0701E
Revision: May 2010 2011 Versa

EC-758
< SERVICE INFORMATION >[MR18DE]
DTC P0171 FUEL INJECTION SYSTEM FUNCTION
DTC P0171 FUEL INJECTION SYSTEM FUNCTION
On Board Diagn
osis LogicINFOID:0000000006341915
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 feedback signal from the air fuel ratio (A/F) sensor 1. The
ECM calculates the necessary compensation to corr ect the offset between the actual and the theoretical
ratios. In case the amount of the compensation value is extremely large (The actual mixture ratio is too lean.),
the ECM judges the condition as the fuel injection sy stem malfunction and lights up the MIL (2 trip detection
logic).
DTC Confirmation ProcedureINFOID:0000000006341916
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-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 and select “SELF-LE ARNING CONT” in “WORK SUPPORT” mode with CON-
SULT-III.
4. Clear the self-learning control coefficient by touching “CLEAR”.
5. Start engine. If it is difficult to start engine, the fuel injection system has a malfunction.
Perform the following procedure is advised.
a. 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.
b. If engine starts, go to EC-761, "
Diagnosis Procedure".
If engine does not start, check exhaus t and intake air leak visually.
6. Keep engine at idle for at least 5 minutes.
7. Check 1st trip DTC. The 1st trip DTC P0171 should be detected at this stage, if a malfunction exists. If so, go to EC-761,
"Diagnosis Procedure".
NOTE:
If 1st trip DTC is not detected during above proc edure, performing the following procedure is advised.
a. Turn ignition switch OFF and wait at least 10 seconds.
b. Start engine.
c. Maintain the following conditions for at least 10 consecutive minutes. Hold the accelerator pedal as steady as possible.
Sensor Input Signal to ECM ECM functionActuator
Air fuel ratio (A/F) sensor 1 Density of oxygen in exhaust gas
(Mixture ratio fe
edback signal) Fuel injection control Fuel injector
DTC No.
Trouble diagnosis
name DTC detecting condition
Possible cause
P0171
0171 Fuel injection system
too lean • 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
• Air fuel ratio (A/F) sensor 1
• Fuel injector
• Exhaust gas leaks
• Incorrect fuel pressure
• Lack of fuel
• Mass air flow sensor
• Incorrect PCV hose connection
Revision: May 2010
2011 Versa

DTC P0171 FUEL INJECTION SYSTEM FUNCTION
EC-759
< SERVICE INFORMATION > [MR18DE]
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CAUTION:
Always drive vehicle at a safe speed.
d. Check 1st trip DTC.
e. If 1st trip DTC is detected, go to EC-761, "
Diagnosis Procedure".
WITH GST
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Disconnect mass air flow sensor (1) harness connector.
4. Restart engine and let idle for at least 5 seconds.
5. Stop engine and reconnect mass air flow sensor (1) harness
connector.
6. Select Service $03 with GST. Make sure DTC P0102 is detected.
7. Select Service $04 with GST and erase the DTC P0102.
8. Start engine. If it is difficult to start engine, the fuel injection system has a mal-
function.
Perform the following procedure is advised.
a. 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.
b. If engine starts, go to EC-761, "
Diagnosis Procedure".
If engine does not start, check exhaust and intake air leak visually.
9. Keep engine at idle for at least 5 minutes.
10. Check 1st trip DTC. The 1st trip DTC P0171 should be detected at this stage, if a malfunction exists. If so, go to EC-761,
"Diagnosis Procedure".
NOTE:
If 1st trip DTC is not detected during above proc edure, performing the following procedure is advised.
a. Turn ignition switch OFF and wait at least 10 seconds.
b. Start engine.
c. Maintain the following conditions for at least 10 consecutive minutes. Hold the accelerator pedal as steady as possible.
CAUTION:
Always drive vehicle at a safe speed.
d. Check 1st trip DTC.
e. If 1st trip DTC is detected, go to EC-761, "
Diagnosis Procedure".
VHCL SPEED SE50 – 120 km/h (31 – 75 MPH)
VHCL SPEED SE50 – 120 km/h (31 – 75 MPH)
BBIA0701E
Revision: May 2010 2011 Versa

DTC P0171 FUEL INJECTION SYSTEM FUNCTION
EC-761
< SERVICE INFORMATION > [MR18DE]
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Do not use ECM ground terminals wh
en measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground ot her than ECM terminals, such as the ground.
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)
Diagnosis ProcedureINFOID:0000000006341918
1.CHECK EXHAUST GAS LEAK
1. Start engine and run it at idle.
2. Listen for an exhaust gas leak before three way catalyst (manifold).
OK or NG
OK >> GO TO 2.
NG >> Repair or replace.
2.CHECK FOR INTAKE AIR LEAK AND PCV HOSE
TERMI- NAL
NO. WIRE
COLOR ITEM
CONDITION DATA (DC Voltage)
3 G A/F sensor 1 heater [Engine is running]
•
Warm-up condition
• Idle speed (More than 140 seconds after starting engine) Approximately 2.9 - 8.8 V
25
29
30
31 V
Y
O L Fuel injector No. 4
Fuel injector No. 3
Fuel injector No. 2
Fuel injector No. 1 [Engine is running]
•
Warm-up condition
• Idle speed NOTE:
The pulse cycle changes depending on rpm at
idle BATTERY VOLTAGE
(11 - 14 V)
[Engine is running]
• Warm-up condition
• Engine speed: 2,000 rpm BATTERY VOLTAGE
(11 - 14 V)
49 W A/F sensor 1 [Engine is running]
•
Warm-up condition
• Engine speed: 2,000 rpm Approximately 1.8 V
Output voltage varies with air
fuel ratio.
53 B A/F sensor 1 [Ignition switch: ON] Approximately 2.2 V
PBIA8148J
PBIB0529E
PBIA4943J
PBIB1216E
Revision: May 2010 2011 Versa

EC-762
< SERVICE INFORMATION >[MR18DE]
DTC P0171 FUEL INJECTION SYSTEM FUNCTION
1. Listen for an intake air leak after the mass air flow sensor.
2. Check PCV hose connection.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace.
3.CHECK AIR FUEL RATIO (A/F) SENS
OR 1 CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect air fuel ratio (A/F) sensor 1 harness connector (1).
- Air fuel ratio (A/F) sensor 1 (2)
3. Disconnect ECM harness connector.
4. Check harness continuity between the following terminals. Refer to Wiring Diagram.
5. Check harness continuity between ECM terminals 49, 53 or A/F sensor 1 terminals 1, 2 and ground. Refer to Wiring Diagram.
6. Also check harness for 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.
4.CHECK FUEL PRESSURE
1. Release fuel pressure to zero. Refer to EC-582, "
Fuel Pressure Check".
2. Install fuel pressure gauge and check fuel pressure. Refer to EC-582, "
Fuel Pressure Check".
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.
5.DETECT MALFUNCTIONING PART
Check the following.
• Fuel pump and circuit (Refer to EC-1014
.)
• Fuel pressure regulator (Refer to EC-582, "
Fuel Pressure Check".)
• Fuel lines (Refer to FL-5
.)
• Fuel filter for clogging
>> Repair or replace.
6.CHECK MASS AIR FLOW SENSOR
With CONSULT-III
1. Install all removed parts.
2. Start engine and warm it up to normal operating temperature.
3. Check “MASS AIR FLOW” in “DATA MONITOR” mode with CONSULT-III.
With GST
A/F sensor 1 terminal ECM terminal
14 9
25 3
Continuity should exist.
Continuity should not exist.
BBIA0699E
At idling: Approximately 350 kPa (3.57 kg/cm2, 51 psi)
At idling : 1.0 - 4.0 g·m/sec
At 2,500 rpm : 2.0 - 10.0 g·m/sec
Revision: May 2010 2011 Versa

DTC P0171 FUEL INJECTION SYSTEM FUNCTION
EC-763
< SERVICE INFORMATION > [MR18DE]
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1. Install all removed parts.
2. Start engine and warm it up to normal operating temperature.
3. Check mass air flow sensor signal in Service $01 with GST.
OK or NG
OK >> GO TO 7.
NG >> Check connectors for rusted terminals or loose connections in the mass air flow sensor circuit or
ground. Refer to EC-664
.
7.CHECK FUNCTION OF FUEL INJECTORS
With CONSULT-III
1. Let engine idle.
2. Perform “POWER BALANCE” in “A CTIVE TEST” mode with CONSULT-III.
3. Make sure that each circuit produces a momentary engine speed drop.
Without CONSULT-III
1. Let engine idle.
2. Listen to each fuel injector operating sound.
OK or NG
OK >> GO TO 8.
NG >> Perform trouble diagnosis for EC-1009
.
8.CHECK FUEL INJECTOR
1. Confirm that the engine is cooled down and t here are no fire hazards near the vehicle.
2. Turn ignition switch OFF.
3. Reconnect all harness connectors disconnected.
4. Remove fuel tube assembly. Refer to EM-154
.
Keep fuel hose and all fuel injector connected to fuel tube.
The fuel injector harness connectors should remain connected.
5. Disconnect all ignition coil harness connectors.
6. Prepare pans or saucers under each fuel injector.
7. Crank engine for about 3 seconds. Make sure that fuel sprays out from fuel injectors.
OK or NG
OK >> GO TO 9.
NG >> Replace fuel injectors from which fuel does not spray out. Always replace O-ring with new ones.
9.CHECK INTERMITTENT INCIDENT
Refer to EC-632
.
>> INSPECTION END
At idling : 1.0 - 4.0 g·m/sec
At 2,500 rpm : 2.0 - 10.0 g·m/sec
Clicking noise should be heard.
PBIB3332E
Fuel should be sprayed evenly for each fuel injector.
PBIA9666J
Revision: May 2010
2011 Versa