NISSAN LATIO 2009 Service Repair Manual

DTC P0112, P0113 IAT SENSOR
EC-1185
< SERVICE INFOMATION >
[MR TYPE 2] C
D E
F
G H
I
J
K L
M A EC
NP
O
DTC P0112, P0113 IAT SENSOR
Component Description INFOID:0000000004500015
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. Electric al 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 te rminals, such as the ground.
On Board Diagnosis Logic INFOID:0000000004500016
DTC Confirmation Procedure INFOID:0000000004500017
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-1186, " 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.

EC-1186< SERVICE INFOMATION >
[MR TYPE 2]
DTC P0112, P0113 IAT SENSOR
Wiring Diagram INFOID:0000000004500018
Diagnosis Procedure INFOID:00000000045000191.
CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screw on the body. Refer to EC-1144, " Ground Inspection " . BBWA2633E

DTC P0112, P0113 IAT SENSOR
EC-1187
< SERVICE INFOMATION >
[MR TYPE 2] C
D E
F
G H
I
J
K L
M A EC
NP
O
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 flow 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.

EC-1188< SERVICE INFOMATION >
[MR TYPE 2]
DTC P0112, P0113 IAT SENSOR
Refer to EC-1188, " Component Inspection " .
OK or NG OK >> GO TO 5.
NG >> Replace mass air flow sensor (with intake air temperature sensor). 5.
CHECK INTERMITTENT INCIDENT
Refer to EC-1138 .
>> INSPECTION END
Component Inspection INFOID:0000000004500020
INTAKE AIR TEMPERATURE SENSOR
1. Check resistance between mass air flow sensor (1) terminals 5 and 6 under the following conditions.
2. If NG, replace mass air flow sens or (with intake air temperature
sensor).
Removal and Installation INFOID:0000000004500021
MASS AIR FLOW SENSOR
Refer to EM-139, " Removal and Installation " .
Intake air temperature
°C ( °F) Resistance k Ω
25 (77) 1.800 - 2.200 PBIA9559J
SEF012P

DTC P0116 ECT SENSOR
EC-1189
< SERVICE INFOMATION >
[MR TYPE 2] C
D E
F
G H
I
J
K L
M A EC
NP
O
DTC P0116 ECT SENSOR
Component Description INFOID:0000000004500022
The engine coolant temperature sensor is used to detect the engine
coolant temperature. The sensor modifies a voltage signal from the
ECM. The modified signal returns to the ECM as the engine coolant
temperature input. The sensor uses a thermistor which is sensitive to
the change in temperature. The electrical resistance of the ther-
mistor decreases as temperature increases.

*: This data is reference value and is measured between ECM terminal 38 (Engine
coolant temperature sensor) 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.
On Board Diagnosis Logic INFOID:0000000004477349
NOTE:
If DTC P0116 is displayed with P0117 or P0118, first perform the trouble diagnosis for DTC P0117,
P0118. Refer to EC-1193, " DTC Confirmation Procedure " .
DTC Confirmation Procedure INFOID:0000000004477350
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.
TESTING CONDITION:
Before performing the following procedure, do not add fuel.
1. Start engine and warm it up to normal operating temperature.
2. Rev engine up to 2,000 rpm for more than10 minutes.
3. Move the vehicle to a cool place, then stop engine and turn ignition switch OFF.
4. Check resistance between “fuel level s ensor unit and fuel pump” terminals 4 and 5.
5. Soak the vehicle until the resistance between “fuel level sensor unit and fuel pump” terminals 4 and 5
becomes 0.5 k Ω higher than the value measured before soaking.
CAUTION:
Never turn ignition switch ON during soaking time. SEF594K
Engine coolant temperature
°C ( °F) Voltage* V Resistance k
Ω
–10 (14) 4.4 7.0 - 11.4 20 (68) 3.5 2.1 - 2.9
50 (122) 2.2 0.68 - 1.00
90 (194) 0.9 0.236 - 0.260 SEF012P
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0116
0116 Engine coolant tempera-
ture sensor circuit range/
performance Engine coolant temperature signal from engine
coolant temperature sensor does not fluctuate,
even when some time has passed after starting
the engine with pre-warming up condition. • Harness or connectors
(High or low resistance in the circuit)
• Engine coolant temperature sensor

EC-1190< SERVICE INFOMATION >
[MR TYPE 2]
DTC P0116 ECT SENSOR
NOTE:
Soak time changes depending on ambient ai r temperature. It may take several hours.
6. Start engine and let it idle for 5 minutes.
7. Check 1st trip DTC.
8. If 1st trip DTC is detected, go to EC-1190, " Diagnosis Procedure " .
Diagnosis Procedure INFOID:00000000044773511.
CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screw on the body. Refer to EC-1144, " Ground Inspection " .
OK or NG OK >> GO TO 2.
NG >> Repair or replace ground connections. 2.
CHECK ENGINE COOLANT TEMPERATURE SENSOR
Refer to EC-1190, " Component Inspection " .
OK or NG OK >> GO TO 3.
NG >> Replace engine coolant temperature sensor. 3.
CHECK INTERMITTENT INCIDENT
Refer to EC-1138 .
Refer to EC-1194, " Wiring Diagram " .
>> INSPECTION END
Component Inspection INFOID:0000000004500027
ENGINE COOLANT TEMPERATURE SENSOR
1. Check resistance between engine coolant temperature sensor terminals 1 and 2 as shown in the figure.:
Vehicle front
1. Body ground E24 2. Engine ground F9 3. Engine ground F16
4. Body ground E15 BBIA0698E
PBIB2005E

DTC P0116 ECT SENSOR
EC-1191
< SERVICE INFOMATION >
[MR TYPE 2] C
D E
F
G H
I
J
K L
M A EC
NP
O

2. If NG, replace engine coolant temperature sensor.
Removal and Installation INFOID:0000000004500028
ENGINE COOLANT TEMPERATURE SENSOR Refer to CO-47, " Component " .
Temperature
°C ( °F) Resistance k Ω
20 (68) 2.1 - 2.9
50 (122) 0.68 - 1.00
90 (194) 0.236 - 0.260 SEF012P

EC-1192< SERVICE INFOMATION >
[MR TYPE 2]
DTC P0117, P0118 ECT SENSOR
DTC P0117, P0118 ECT SENSOR
Component Description INFOID:0000000004501092
The engine coolant temperature sensor is used to detect the engine
coolant temperature. The sensor modifies a voltage signal from the
ECM. The modified signal returns to the ECM as the engine coolant
temperature input. The sensor uses a thermistor which is sensitive to
the change in temperature. The elec trical resistance of the ther-
mistor decreases as temperature increases.

*: This data is reference value and is measured between ECM terminal 38 (Engine
coolant temperature sensor) 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.
On Board Diagn osis Logic INFOID:0000000004500023
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. SEF594K
Engine coolant temperature
°C ( °F) Voltage* V Resistance k
Ω
–10 (14) 4.4 7.0 - 11.4 20 (68) 3.5 2.1 - 2.9
50 (122) 2.2 0.68 - 1.00
90 (194) 0.9 0.236 - 0.260 SEF012P
DTC No.
Trouble Diagnosis
Name DTC detecting condition Possible Cause
P0117
0117 Engine coolant tem-
perature sensor cir-
cuit low input An excessively low voltage from the sensor is
sent to ECM. • Harness or connectors
(Engine coolant temperature sensor circuit is
open or shorted.)
• Engine coolant temperature sensor
P0118
0118 Engine coolant tem-
perature sensor cir-
cuit high input An excessively high voltage from the sensor is
sent to ECM.

EC
NP
O
DTC Confirmation Procedure
INFOID:0000000004500024
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.
WITH CONSULT-III
1. Turn ignition switch ON and wait at least 5 seconds.
2. Check DTC.
3. If DTC is detected, go to EC-1194, " Diagnosis Procedure " .
Detected items Engine operating condition in fail-safe mode
Engine coolant temper- ature sensor circuit Engine coolant temperature will be determined by ECM based on the following condition.
CONSULT-III displays the engine coolant temperature decided by ECM.
Condition Engine coolant temperature decided
(CONSULT-III display)
Just as ignition switch is turned ON or START 40 °C (104 °F)
Approx. 4 minutes or more after engine starting. 80 °C (176 °F)
Except as shown above 40 - 80
°C (104 - 176 °F)
(Depends on the time)
When the fail-safe system for engine coolant temperature sensor is activated, the cooling fan operates while
engine is running.

EC-1194< SERVICE INFOMATION >
[MR TYPE 2]
DTC P0117, P0118 ECT SENSOR
Wiring Diagram INFOID:0000000004500025
Diagnosis Procedure INFOID:00000000045000261.
CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screw on the body. Refer to EC-1144, " Ground Inspection " . BBWA2634E