NISSAN LATIO 2009 Service Repair Manual

EC
NP
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YES >> GO TO 2.
NO >> Repair or replace ground connection. MIXTURE RATIO SELF-LEARNING VALUE
CLEAR : Special Repair Requirement " .
2. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171 or P0172 detected? Is it difficult to start engine? YES >> Perform trouble diagnosis for DTC P0171 or P0172. Refer to
EC-229, " DTC Logic " or
EC-235, " DTC Logic " .
NO >> GO TO 3. YES >> GO TO 4.
NO >> Repair open circuit or short to ground or short to power in harness or connectors. YES >> GO TO 5.
NO >> Repair open circuit or short to ground or short to power in harness or connectors. Component Inspection " .
Is the inspection result normal? YES >> GO TO 7.
NO >> GO TO 6. HO2S2 ECM
Continuity
Connector Terminal Connector Terminal
F13 1 F11 59 Existed HO2S2 ECM
Continuity
Connector Terminal Connector Terminal
F13 4 F11 50 Existed
HO2S2 Ground Continuity
Connector Terminal
F13 4 Ground Not existed
ECM Ground Continuity
Connector Terminal
F11 50 Ground Not existed

EC-226< COMPONENT DIAGNOSIS >
[HR16DE]
P0139 HO2S2 6.
REPLACE HEATED OXYGEN SENSOR 2
Replace heated oxygen sensor 2.
CAUTION:
• Discard any sensor which has been dropped from a he ight 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 sensor, clean exhaust system threads usi ng Oxygen Sensor Thread Cleaner
[commercial service tool (J-43897-18 or J43897-12)] and approved Anti-seize Lubricant (commercial
service tool).
>> INSPECTION END 7.
CHECK INTERMITTENT INCIDENT
Refer to EC-120, " Diagnosis Procedure " .
>> INSPECTION END
Component Inspection INFOID:00000000047801341.
INSPECTION START
Do you have CONSULT-III?
Do you have CONSULT-III? YES >> GO TO 2.
NO >> GO TO 3. 2.
CHECK HEATED OXYGEN SENSOR 2
With CONSULT-III
1. Turn ignition switch ON and select “DATA MONITOR” mode with CONSULT-III.
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. Select “FUEL INJECTION” in “ACT IVE TEST” mode, and select “HO2S2 (B1)” as the monitor item with
CONSULT-III.
7. Check “HO2S2 (B1)” at idle speed when adjusting “FUEL INJECTION” to ± 25%.
“HO2S2 (B1)” should be above 0.68 V at l east once when the “FUEL INJECTION” is + 25%.
“HO2S2 (B1)” 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 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. PBIB3458E

P0139 HO2S2
EC-227
< COMPONENT DIAGNOSIS >
[HR16DE] C
D E
F
G H
I
J
K L
M A EC
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5. Check the voltage between ECM harness connector and ground
under the following condition.
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 and ground
under the following condition.
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 and ground
under the following condition.
Is the inspection result normal? YES >> INSPECTION END
NO >> GO TO 6. 6.
REPLACE HEATED OXYGEN SENSOR 2
Replace heated oxygen sensor 2.
CAUTION:
• Discard any sensor which has been dropped from a he ight of more than 0.5 m (19.7 in) onto a hard
surface such as a concrete floor; use a new one. ECM
Ground Condition Voltage
Con-
nector Termi-
nal
F11 50
(HO2S2 signal) Ground Revving 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 be-
low 0.18 V at least once
during this procedure. PBIB2996E
ECM
Ground Condition Voltage
Con-
nector Termi-
nal
F11 50
(HO2S2 signal) Ground
Keeping engine speed
at idle for 10 minutes The voltage should be
above 0.68 V at least once
during this procedure.
The voltage should be be-
low 0.18 V at least once
during this procedure. JMBIA2199ZZ
ECM
Ground Condition Voltage
Con-
nector Termi-
nal
F11 50
(HO2S2 signal) Ground Coasting from 80 km/h
(50 MPH) in D position
(A/T), 4th gear position
(M/T) The voltage should be
above 0.68 V at least once
during this procedure.
The voltage should be be-
low 0.18 V at least once
during this procedure. JMBIA2200ZZ

EC
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P0171 FUEL INJECTION SYSTEM FUNCTION
DTC Logic INFOID:0000000004780135
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 MIXTURE RATIO SELF-LEARNING VALUE
CLEAR : Special Repair Requirement " .
2. Start engine.
Is it difficult to start engine? YES >> GO TO 3.
NO >> GO TO 4. YES >> Go to
EC-231, " Diagnosis Procedure " .
NO >> Check exhaust and intake air leak visually. YES >> Go to
EC-231, " Diagnosis Procedure " .
NO >> GO TO 5. 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 injectorDTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0171 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
• A/F sensor 1
• Fuel injector
• Exhaust gas leaks
• Incorrect fuel pressure
• Lack of fuel
• Mass air flow sensor
• Incorrect PCV hose connection

YES >> Go to
EC-231, " Diagnosis Procedure " .
NO >> INSPECTION END VHCL SPEED SE 50 - 120 km/h (31 - 75 MPH)

EC
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Wiring Diagram
INFOID:0000000004780683
Diagnosis Procedure INFOID:0000000004780136 B

EC-232< COMPONENT DIAGNOSIS >
[HR16DE]
P0171 FUEL INJECTION SYSTEM FUNCTION
2. Listen for an exhaust gas leak before three way catalyst (manifold).
Is exhaust gas leak detected? YES >> Repair or replace.
NO >> GO TO 2. 2.
CHECK FOR INTAKE AIR LEAK
1. Listen for an intake air leak after the mass air flow sensor.
2. Check PCV hose connection.
Intake air leak detected? YES >> Repair or replace.
NO >> GO TO 3. 3.
CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect corresponding A/F sensor 1 harness connector.
3. Disconnect ECM harness connector.
4. Check the continuity between A/F sensor 1 harness connector and ECM harness connector.
5. Check the continuity between A/F sensor 1 harness connector and ground, or ECM harness connector
and ground.
6. Also check harness for short to power.
Is the inspection result normal? YES >> GO TO 4.
NO >> Repair open circuit or short to ground or short to power in harness or connectors. 4.
CHECK FUEL PRESSURE
1. Check fuel pressure. Refer to EC-498, " Inspection " .
Is the inspection result normal? YES >> GO TO 6. PBIB1216E
A/F sensor 1 ECM
Continuity
Connector Terminal Connector Terminal
F12 1
F11 49
Existed
2 53
A/F sensor 1 Ground Continuity
Connector Terminal
F12 1
Ground Not existed
2
ECM Ground Continuity
Connector Terminal
F11 49
Ground Not existed
53

EC
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NO >> GO TO 5. YES >> Replace “fuel filter and fuel pump assembly”.
NO >> Repair or replace Mass Air Flow Sensor " .
With GST
1. Install all removed parts.
2. Check mass air flow sensor signal in Service $01 with GST.
3. For specification, refer to EC-504, " Mass Air Flow Sensor " .
Is the measurement value within the specification?YES >> GO TO 7.
NO >> Check connectors for rusted terminals or loose c onnections in the mass air flow sensor circuit or
grounds. Refer to EC-148, " DTC Logic " .
YES >> GO TO 8.
NO >> Perform trouble diagnosis for FUEL INJECTOR, refer to EC-430, " Component Function Check " .
Removal and Installation " .
Keep fuel hose and all fuel injectors connected to fuel tube.
5. Disconnect all ignition coil harness connectors.
6. Prepare pans or saucers under each fuel injector.

YES >> GO TO 9.
NO >> Replace fuel injectors from which fuel does not spray out. Always replace O-ring with new ones. Diagnosis Procedure " .
>> INSPECTION END
Fuel should be sprayed even
ly for each fuel injector.