2009 NISSAN LATIO service

EC-1172< SERVICE INFOMATION >
[MR TYPE 2]
DTC P0101 MAF SENSOR
1. Start engine and warm it up to normal operating temperature.
2. Select Service $01 with GST.
3. Check the mass air flow sensor signal with Service $01.
4. Check for linear mass air flow sensor signal value rise in response to increases to about 4,000 rpm in engine speed.
5. If NG, go to EC-1174, " Diagnosis Procedure " .
SEF534P

DTC P0101 MAF SENSOR
EC-1173
< SERVICE INFOMATION >
[MR TYPE 2] C
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Wiring Diagram
INFOID:0000000004500003
Specification data are reference values and are measured between each terminal and ground.
CAUTION:
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. BBWA2632E

EC-1174< SERVICE INFOMATION >
[MR TYPE 2]
DTC P0101 MAF SENSOR
Diagnosis Procedure INFOID:00000000045000041.
INSPECTION START
Which malfunction (A or B) is duplicated?
A or B A >> GO TO 3.
B >> GO TO 2. 2.
CHECK INTAKE AIR LEAK
Check the following for connections.
• Air duct
• Vacuum hoses
• Intake air passage between air duct and intake manifold
OK or NG OK >> GO TO 3.
NG >> Reconnect the parts. 3.
CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screw on the body.
Refer to EC-1144, " Ground Inspection " .
TER-
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NO. WIRE
COLOR ITEM CONDITION DATA (DC Voltage)
32 P ECM relay
(Self shut-off) [Engine is running]
[Ignition switch: OFF]
• For a few seconds after turning ignition switch
OFF 0 - 1.0V
[Ignition switch: OFF]
• More than a few seconds after turning ignition switch OFF BATTERY VOLTAGE
(11 - 14V)
45 G Mass air flow sensor [Engine is running]
• Warm-up condition
• Idle speed 0.8 - 1.1V
[Engine is running]
• Warm-up condition
• Engine speed: 2,500 rpm 1.4 - 1.7V
52 LG Sensor ground
(Mass air flow sensor) [Engine is running]
• Warm-up condition
• Idle speed Approximately 0V
105 G Power supply for
ECM [Ignition switch: ON] BATTERY VOLTAGE
(11 - 14V) BBIA0698E

DTC P0101 MAF SENSOR
EC-1175
< SERVICE INFOMATION >
[MR TYPE 2] C
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OK or NG OK >> GO TO 4.
NG >> Repair or replace ground connections. 4.
CHECK MAF SENSOR PO WER SUPPLY CIRCUIT
1. Disconnect mass air flow (MAF) sensor (1) harness connector.
2. Turn ignition switch ON.
3. Check voltage between MAF sensor terminal 2 and ground with CONSULT-III or tester.
OK or NG OK >> GO TO 6.
NG >> GO TO 5. 5.
DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors E8, F8
• Harness for open or short between mass air flow sensor and IPDM E/R
• Harness for open or short between mass air flow sensor and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors. 6.
CHECK MAF SENSOR GROUND CI RCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between MAF sensor terminal 3 and ECM terminal 52.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG OK >> GO TO 7.
NG >> Repair open circuit or short to ground or short to power in harness or connectors. 7.
CHECK MAF SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between MAF sensor terminal 4 and ECM terminal 45. Refer to Wiring Diagram.:
Vehicle front
1. Body ground E24 2. Engine ground F9 3. Engine ground F16
4. Body ground E15 BBIA0701E
Voltage: Battery voltage
PBIB1168E
Continuity should exist.

DTC P0101 MAF SENSOR
EC-1177
< SERVICE INFOMATION >
[MR TYPE 2] C
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b. If NG, repair or replace malfunctioning part and perform step 2 to 4 again.
If OK, go to next step.
6. Turn ignition switch OFF.
7. Disconnect mass air flow sensor har ness connector and reconnect it again.
8. Perform step 2 to 4 again.
9. If NG, clean or replace mass air flow sensor.
Without CONSULT-III
1. Reconnect all harness connectors disconnected.
2. Start engine and warm it up to normal operating temperature.
3. Check voltage between ECM terminal 45 (Mass air flow sensor signal) and ground.
*: Check for linear voltage rise in response to engine being increased to about 4,000 rpm.
4. If the voltage is out of spec ification, proceed the following.
a. Check for the cause of uneven air flow through mass air flow sensor. Refer to following. • Crushed air ducts
• Malfunctioning seal of air cleaner element
• Uneven dirt of air cleaner element
• Improper specification of intake air system parts
b. If NG, repair or replace malfunctioning part and perform step 2 and 3 again. If OK, go to next step.
5. Turn ignition switch OFF.
6. Disconnect mass air flow sensor har ness connector and reconnect it again.
7. Perform step 2 and 3 again.
8. If NG, clean or replace mass air flow sensor.
Removal and Installation INFOID:0000000004500006
MASS AIR FLOW SENSOR Refer to EM-139, " Removal and Installation " .Condition Voltage V
Ignition switch ON (Engine stopped.) Approx 0.4
Idle (Engine is warmed-up to normal
operating temperature.) 0.8 - 1.1
2,500 rpm (Engine is warmed-up to
normal operating temperature.) 1.4 - 1.7
Idle to about 4,000 rpm 0.8 - 1.1 to 2.4* PBIA9564J

EC-1178< SERVICE INFOMATION >
[MR TYPE 2]
DTC P0102, P0103 MAF SENSOR
DTC P0102, P0103 MAF SENSOR
Component Description INFOID:0000000004501157
The mass air flow sensor (1) is placed in the stream of intake air. It
measures the intake flow rate by measuring a part of the entire
intake flow. The mass air flow sensor controls the temperature of the
hot wire to a certain amount. The heat generated by the hot wire is
reduced as the intake air flows around it. The more air, the greater
the heat loss.
Therefore, the electric current supplied to hot wire is changed to
maintain the temperature of the hot wire as air flow increases. The
ECM detects the air flow by means of this current change.
CONSULT-III Reference Value in Data Monitor Mode INFOID:0000000004501158
Specification data are reference values.
On Board Diagn osis Logic INFOID:0000000004500009
These self-diagnoses have the one trip detection logic.
FAIL-SAFE MODE
When the malfunction is detected, the ECM enters fail-safe mode and the MIL lights up.
DTC Confirmation Procedure INFOID:0000000004500010
NOTE:
If DTC Confirmation Procedure has been previously conduc ted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test. PBIA9559J
MONITOR ITEM CONDITION SPECIFICATION
MAS A/F SE-B1 • See EC-1130 .
CAL/LD VALUE • Engine: After warming up
• Shift lever: P or N (A/T, CVT), Neutral (M/T)
• Air conditioner switch: OFF
• No load Idle 10% - 35%
2,500 rpm 10% - 35%
MASS AIRFLOW • Engine: After warming up
• Shift lever: P or N (A/T, CVT),
Neutral (M/T)
• Air conditioner switch: OFF
• No load Idle 1.0 - 4.0 g·m/s
2,500 rpm 4.0 - 10.0 g·m/s DTC No.
Trouble diagnosis
name DTC detecting condition Possible cause
P0102
0102 Mass air flow sensor
circuit low input An excessively low voltage from the sensor is sent
to ECM. • Harness or connectors
(Mass air flow sensor circuit is open or short-
ed.)
• Intake air leaks
• Mass air flow sensor
P0103
0103 Mass air flow sensor
circuit high input An excessively high voltage from the sensor is
sent to ECM. • Harness or connectors
(Mass air flow sensor circuit is open or short-
ed.)
• Mass air flow sensor Detected items Engine operating condition in fail-safe mode
Mass air flow sensor circuit Engine speed will no t rise more than 2,400 rpm due to the fuel cut.

EC-1180< SERVICE INFOMATION >
[MR TYPE 2]
DTC P0102, P0103 MAF SENSOR
Wiring Diagram INFOID:0000000004501159
Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring in put/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. BBWA2632E

DTC P0102, P0103 MAF SENSOR
EC-1181
< SERVICE INFOMATION >
[MR TYPE 2] C
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Diagnosis Procedure
INFOID:00000000045000121.
INSPECTION START
Which malfunction (P0102 or P0103) is duplicated?
P0102 or P0103 P0102 >> GO TO 2.
P0103 >> GO TO 3. 2.
CHECK INTAKE SYSTEM
Check the following for connection.
• Air duct
• Vacuum hoses
• Intake air passage between air duct and intake manifold
OK or NG OK >> GO TO 3.
NG >> Reconnect the parts. 3.
CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screw on the body.
Refer to EC-1144, " Ground Inspection " .
TER-
MI-
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NO. WIRE
COLOR ITEM CONDITION DATA (DC Voltage)
32 P ECM relay
(Self shut-off) [Engine is running]
[Ignition switch: OFF]
• For a few seconds after turning ignition switch
OFF 0 - 1.0V
[Ignition switch: OFF]
• More than a few seconds after turning ignition switch OFF BATTERY VOLTAGE
(11 - 14V)
45 G Mass air flow sensor [Engine is running]
• Warm-up condition
• Idle speed 0.8 - 1.1V
[Engine is running]
• Warm-up condition
• Engine speed: 2,500 rpm 1.4 - 1.7V
52 LG Sensor ground
(Mass air flow sensor) [Engine is running]
• Warm-up condition
• Idle speed Approximately 0V
105 G Power supply for
ECM [Ignition switch: ON] BATTERY VOLTAGE
(11 - 14V) BBIA0698E