2009 NISSAN LATIO service

DTC P0102, P0103 MAF SENSOR
EC-663
< SERVICE INFOMATION >
[MR TYPE 1] C
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DTC P0102, P0103 MAF SENSOR
Component Description INFOID:0000000004537121
The mass air flow sensor (1) is plac ed 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 sens or 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 Val ue in Data Monitor Mode INFOID:0000000004537122
Specification data are reference values.
On Board Diagnosis Logic INFOID:0000000004537123
These self-diagnoses have the on e trip detection logic.
FAIL-SAFE MODE When the malfunction is detec ted, the ECM enters fail-safe mode and the MIL lights up.
DTC Confirmation Procedure INFOID:0000000004537124
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-618 .
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 not rise more than 2,400 rpm due to the fuel cut.

DTC P0102, P0103 MAF SENSOR
EC-665
< SERVICE INFOMATION >
[MR TYPE 1] C
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Wiring Diagram
INFOID:0000000004537125
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-666< SERVICE INFOMATION >
[MR TYPE 1]
DTC P0102, P0103 MAF SENSOR
Diagnosis Procedure INFOID:00000000045371261.
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-632, " Ground Inspection " .
TER-
MI-
NAL
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 igni- tion 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 P0102, P0103 MAF SENSOR
EC-667
< SERVICE INFOMATION >
[MR TYPE 1] 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 ECM
• Harness for open or short between mass air flow sensor and IPDM E/R
>> 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 P0102, P0103 MAF SENSOR
EC-669
< SERVICE INFOMATION >
[MR TYPE 1] C
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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:0000000004537128
MASS AIR FLOW SENSOR Refer to EM-139 .
Condition MAS A/F SE-B1 (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-670< SERVICE INFOMATION >
[MR TYPE 1]
DTC P0112, P0113 IAT SENSOR
DTC P0112, P0113 IAT SENSOR
Component Description INFOID:0000000004537129
The intake air temperature sensor is built-into mass air flow sensor
(1). The sensor detects intake air temperature and transmits a signal
to the ECM.
The temperature sensing unit uses a thermistor which is sensitive to
the change in temperature. Electrical resistance of the thermistor
decreases in response to the temperature rise.

*: This data is reference value and is measured between ECM terminal 46 (Intake air
temperature sensor) and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output
voltage. Doing so may result in damage to the ECM's transistor.
Use a ground other than ECM terminals, such as the ground.
On Board Diagn osis Logic INFOID:0000000004537130
DTC Confirmation Procedure INFOID:0000000004537131
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.
1. Turn ignition switch ON and wait at least 5 seconds.
2. Check 1st trip DTC.
3. If 1st trip DTC is detected, go to EC-671, " Diagnosis Procedure " . PBIA9559J
Intake air temperature
°C ( °F) Voltage* V Resistance k
Ω
25 (77) 3.3 1.800 - 2.200
80 (176) 1.2 0.283 - 0.359 SEF012P
DTC No.
Trouble diagnosis
name DTC detecting condition Possible cause
P0112
0112 Intake air tempera-
ture sensor circuit
low input An excessively low voltage from the sensor is
sent to ECM. • Harness or connectors
(Intake air temperature sensor circuit is open
or shorted.)
• Intake air temperature sensor
P0113
0113 Intake air tempera-
ture sensor circuit
high input An excessively high voltage from the sensor is
sent to ECM.

DTC P0112, P0113 IAT SENSOR
EC-671
< SERVICE INFOMATION >
[MR TYPE 1] C
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Wiring Diagram
INFOID:0000000004537132
Diagnosis Procedure INFOID:00000000045371331.
CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screw on the body. Refer to EC-632, " Ground Inspection " . BBWA2633E

EC-672< SERVICE INFOMATION >
[MR TYPE 1]
DTC P0112, P0113 IAT SENSOR
OK or NG OK >> GO TO 2.
NG >> Repair or replace ground connections. 2.
CHECK INTAKE AIR TEMPERATURE SENSOR POWER SUPPLY CIRCUIT
1. Disconnect mass air flow sensor (with intake air temperature sensor) (1) harness connector.
2. Turn ignition switch ON.
3. Check voltage between mass air flow sensor terminal 5 and ground with CONSULT-III or tester.
OK or NG OK >> GO TO 3.
NG >> Repair open circuit or short to ground or short to power
in harness or connectors. 3.
CHECK INTAKE AIR TEMPERATURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between mass air fl ow sensor terminal 6 and ECM terminal 55.
Refer to Wiring Diagram.
4. Also check harness for short to ground and 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 INTAKE AIR TEMPERATURE SENSOR:
Vehicle front
1. Body ground E24 2. Engine ground F9 3. Engine ground F16
4. Body ground E15 BBIA0698E
BBIA0701E
Voltage: Approximately 5V
PBIB1169E
Continuity should exist.