NISSAN LATIO 2009 Service Repair Manual

P0116 ECT SENSOR
EC-165
< COMPONENT DIAGNOSIS >
[HR16DE] C
D E
F
G H
I
J
K L
M A EC
NP
O
P0116 ECT SENSOR
Description INFOID:0000000004780447
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.
<Reference data>
*: These data are reference values and are measured between ECM terminal 38
(Engine coolant temperature sensor) and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output vo ltage. Doing so may result in damage to the ECM's transis-
tor. Use a ground other than ECM terminals, such as the ground.
DTC Logic INFOID:0000000004780084
DTC DETECTION LOGIC NOTE:
If DTC P0116 is displayed with P0117 or P0118, first perform the trouble diagnosis for DTC P0117,
P0118. Refer to EC-167, " DTC Logic " .
DTC CONFIRMATION PROCEDURE 1.
PRECONDITIONING
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.
>> GO TO 2. 2.
PERFORM DTC CONFIRMATION PROCEDURE
1. Start engine and warm it up to normal operating temperature.
2. Rev engine up to 2,000 rpm for more than 10 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. SEF594K
Engine coolant temperature
[° C ( °F)] Voltage* (V) Resistance (k
Ω)
–10 (14) 4.4 7.0 - 11.4 20 (68) 3.5 2.37 - 2.63
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 Engine coolant temperature
sensor circuit range/perfor-
mance 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

YES >>
EC-166, " Diagnosis Procedure " .
NO >> INSPECTION END
Diagnosis Procedure INFOID:0000000004780085Ground Inspection " .
Is the inspection result normal? YES >> GO TO 2.
NO >> Repair or replace ground connection. Component Inspection " .
Is the inspection result normal? YES >> GO TO 3.
NO >> Replace engine coolant temperature sensor. Diagnosis Procedure " .
>> INSPECTION END
Component Inspection INFOID:0000000004780446YES >> INSPECTION END
NO >> Replace engine coolant temperature sensor. Terminals Condition Resistance
1 and 2 Temperature [ °C ( °F)] 20 (68) 2.37 - 2.63 k
Ω
50 (122) 0.68 - 1.00 k Ω
90 (194) 0.236 - 0.260 k Ω

P0117, P0118 ECT SENSOR
EC-167
< COMPONENT DIAGNOSIS >
[HR16DE] C
D E
F
G H
I
J
K L
M A EC
NP
O
P0117, P0118 ECT SENSOR
Description INFOID:0000000004780087
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.
<Reference data>
*: These data are reference values and are measured between ECM terminal 38
(Engine coolant temperature sensor) and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output vo ltage. Doing so may result in damage to the ECM's transis-
tor. Use a ground other than ECM terminals, such as the ground.
DTC Logic INFOID:0000000004780088
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE 1.
PRECONDITIONING
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.
>> GO TO 2. 2.
PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON and wait at least 5 seconds.
2. Check DTC.
Is DTC detected? YES >> Go to
EC-168, " Diagnosis Procedure " .
NO >> INSPECTION END SEF594K
Engine coolant temperature
[° C ( °F)] Voltage* (V) Resistance (k
Ω)
–10 (14) 4.4 7.0 - 11.4 20 (68) 3.5 2.37 - 2.63
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 Engine coolant temperature
sensor circuit low input An excessively low voltage from the sensor
is sent to ECM. • Harness or connectors
(The sensor circuit is open or shorted.)
• Engine coolant temperature sensor
P0118 Engine coolant temperature
sensor circuit high input An excessively high voltage from the sensor
is sent to ECM.

Ground Inspection " .
Is the inspection result normal?

EC
NP
O
YES >> GO TO 2.
NO >> Repair or replace ground connection. YES >> GO TO 3.
NO >> Repair open circuit or short to ground or short to power
in harness or connectors. YES >> GO TO 4.
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 5.
NO >> Replace engine coolant temperature sensor. Diagnosis Procedure " .
>> INSPECTION END
Component Inspection INFOID:0000000004780090

EC-170< COMPONENT DIAGNOSIS >
[HR16DE]
P0117, P0118 ECT SENSOR
4. Check resistance between engine coolant temperature sensor terminals by heating with hot water as shown in the figure.
Is the inspection result normal? YES >> INSPECTION END
NO >> Replace engine coolant temperature sensor. Terminals Condition Resistance
1 and 2 Temperature [ °C ( °F)] 20 (68) 2.37 - 2.63 k
Ω
50 (122) 0.68 - 1.00 k Ω
90 (194) 0.236 - 0.260 k Ω PBIB2005E

EC
NP
O
P0122, P0123 TP SENSOR
Description INFOID:0000000004780091
Electric throttle control actuator consists of throttle control motor,
throttle position sensor, etc. The throttle position sensor responds to
the throttle valve movement.
The throttle position sensor has two sensors. These sensors are a
kind of potentiometer which transform the throttle valve position into
output voltage, and emit the voltage signals to the ECM. The ECM
judges the current opening angle of the throttle valve from these sig-
nals and controls the throttle valve opening angle in response to
driving conditions via the throttle control motor.
DTC Logic INFOID:0000000004780092
DTC DETECTION LOGIC NOTE:
If DTC P0122 or P0123 is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643.
Refer to EC-358, " DTC Logic " .
DTC CONFIRMATION PROCEDURE YES >> Go to
EC-172, " Diagnosis Procedure " .
NO >> INSPECTION END

Ground Inspection " .
Is the inspection result normal?

EC
NP
O
YES >> GO TO 2.
NO >> Repair or replace ground connection. YES >> GO TO 3.
NO >> Repair open circuit or short to ground or short to power
in harness or connectors. 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. Special Repair Requirement " .
>> INSPECTION END
Electric throttle control actuator
Ground Voltage
Connector Terminal
F7 2 Ground Approx. 5 V Electric throttle control actuator ECM
Continuity
Connector Terminal Connector Terminal
F7 3 F11 34 Existed

Diagnosis Procedure " .
>> INSPECTION END
Component Inspection INFOID:0000000004780094THROTTLE VALVE CLOSED POSITION LEARNING : Special Repair Requirement " .
4. Turn ignition switch ON.
5. Set selector lever to D (A/T) or 1st (M/T) position.
6. Check the voltage between ECM harness connector and
ground.
Is the inspection result normal? YES >> INSPECTION END
NO >> GO TO 2. Special Repair Requirement " .
>> INSPECTION END
Special Repair Requirement INFOID:0000000004780095THROTTLE VALVE CLOSED POSITION LE
ARNING : Special Repair Requirement "
>> GO TO 2.
IDLE AIR VOLUME LEARNING : Special Repair Requirement "
>> ENDECM
Ground Condition Voltage
Connector Terminal
F11 33
(TP sensor
1 signal)
GroundAccelerator
pedal Fully released
More than
0.36V
Fully de-
pressed Less than
4.75V
34
(TP sensor 2 signal) Fully released
Less than
4.75V
Fully de-
pressed More than
0.36V