2009 NISSAN LATIO coolant temperature

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NOTE:
Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.
ACTIVE TEST MODE
Test Item AT OD CANCEL
[ON/OFF] • Indicates [ON/OFF] condition of A/T O/D cancel signal sent
from the TCM. • For M/T models always “OFF” is displayed
CRUISE LAMP
[ON/OFF] • Indicates [ON/OFF]
condition of CRUISE lamp determined
by the ECM according to the input signals.
SET LAMP
[ON/OFF] • Indicates [ON/OFF] condition of SET lamp determined by the
ECM according to the input signals.
A/F ADJ-B1 • Indicates the correction factor stored in ECM. The factor is
calculated from the difference between the target air/fuel ratio
stored in ECM and the air/fuel ratio calculated from air fuel ra-
tio (A/F) sensor 1 signal.
Monitored item [Unit] Description Remarks TEST ITEM CONDITION JUDGEMENT CHECK ITEM (REMEDY)
FUEL INJEC-
TION • Engine: Return to the original
trouble condition
• Change the amount of fuel injec- tion using CONSULT-III. If trouble symptom disappears, see
CHECK ITEM. • Harness and connectors
• Fuel injector
• Air fuel ratio (A/F) sensor 1
IGNITION TIM-
ING • Engine: Return to the original
trouble condition
• Timing light: Set
• Retard the ignition timing using
CONSULT-III. If trouble symptom disappears, see
CHECK ITEM. • Perform Idle Air Volume Learning.
POWER BAL-
ANCE • Engine: After warming up, idle the
engine.
• A/C switch OFF
• Shift lever: P or N (A/T, CVT), Neutral (M/T)
• Cut off each fuel injector signal
one at a time using CONSULT-III. Engine runs rough or dies.
• Harness and connectors
• Compression
• Fuel injector
• Power transistor
• Spark plug
• Ignition coil
COOLING FAN* • Ignition switch: ON
• Turn the cooling fan “LOW”, “HI” and “OFF” with CONSULT-III. Cooling fan moves and stops. • Harness and connectors
• Cooling fan relay
• Cooling fan motor
ENG COOLANT
TEMP • Engine: Return to the original
trouble condition
• Change the engine coolant tem- perature using CONSULT-III. If trouble symptom disappears, see
CHECK ITEM. • Harness and connectors
• Engine coolant temperature sen-
sor
• Fuel injector
FUEL PUMP RE-
LAY • Ignition switch: ON
(Engine stopped)
• Turn the fuel pump relay ON and OFF using CONSULT-III and lis-
ten to operating sound. Fuel pump relay makes the operat-
ing sound. • Harness and connectors
• Fuel pump relay
PURG VOL
CONT/V • Engine: After warming up, run en-
gine at 1,500 rpm.
• Change the EVAP canister purge volume control solenoid valve
opening percent using CON-
SULT-III. Engine speed changes according to
the opening percent. • Harness and connectors
• EVAP canister purge volume con- trol solenoid valve
FUEL/T TEMP
SEN • Change the fuel tank temperature using CONSULT-III.

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DTC P0037, P0038 HO2S2 HEATER
Description INFOID:0000000004537096
SYSTEM DESCRIPTION
The ECM performs ON/OFF control of the heated oxygen sensor 2 heater corresponding to the engine speed,
amount of intake air and engine coolant temperature.
OPERATION
CONSULT-III Reference Val ue in Data Monitor Mode INFOID:0000000004537097
Specification data are reference values.
On Board Diagnosis Logic INFOID:0000000004537098
DTC Confirmation Procedure INFOID:0000000004537099
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, confi rm that battery voltage is between 10.5V and 16V at
idle.
1. Start engine and warm it up to the normal operating temperature. Sensor Input Signal to ECM ECM Function Actuator
Camshaft position sensor (PHASE) Engine speed
Heated oxygen sensor 2
heater control Heated oxygen sensor 2 heater
Crankshaft position sensor (POS)
Engine coolant temperature sensor Engine coolant tempera-
ture
Mass air flow sensor Amount of intake air Engine speed rpm Heated oxygen sensor 2 heater
Above 3,600 OFF
• Below 3,600 rpm after the following conditions are met.
- Engine: After warming up
- Keeping the engine speed between 3,500 and 4,000 rpm for 1 minute and at idle for 1 minute under no load ONMONITOR ITEM CONDITION SPECIFICATION
HO2S2 HTR (B1) • Engine speed: Below 3,600 rpm after the following conditions are met
- Engine: After warming up
- Keeping the engine speed between 3,500 and 4,000 rpm for 1 minute and
at idle for 1 minute under no load. ON
• Engine speed: Above 3,600 rpm OFF DTC No.
Trouble diagnosis
name DTC detecting condition Possible cause
P0037
0037 Heated oxygen
sensor 2 heater
control circuit low The current amperage in the heated oxygen sensor
2 heater circuit is out of the normal range.
(An excessively low voltage signal is sent to ECM
through the heated oxygen sensor 2 heater.) • Harness or connectors
(Heated oxygen sensor 2 heater circuit is
open or shorted.)
• Heated oxygen sensor 2 heater
P0038
0038 Heated oxygen
sensor 2 heater
control circuit high The current amperage in the heated oxygen sensor
2 heater circuit is out of the normal range.
(An excessively high voltage signal is sent to ECM
through the heated oxygen sensor 2 heater.) • Harness or connectors
(Heated oxygen sensor 2 heater circuit is
shorted.)
• Heated oxygen sensor 2 heater

EC-674< SERVICE INFOMATION >
[MR TYPE 1]
DTC P0117, P0118 ECT SENSOR
DTC P0117, P0118 ECT SENSOR
Component Description INFOID:0000000004537136
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:0000000004537137
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 Condit
ion 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.

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DTC Confirmation Procedure
INFOID:0000000004537138
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-676, " 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.

DTC P0117, P0118 ECT SENSOR
EC-677
< SERVICE INFOMATION >
[MR TYPE 1] C
D E
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OK or NG OK >> GO TO 2.
NG >> Repair or replace ground connections. 2.
CHECK ECT SENSOR POWER SUPPLY CIRCUIT
1. Disconnect engine coolant temperature (ECT) sensor (1) har- ness connector.
- : Vehicle front
2. Turn ignition switch ON.
3. Check voltage between ECT sensor terminal 1 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 ECT SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 44 and ECT sensor terminal 2. 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 ENGINE COOLANT TEMPERATURE SENSOR:
Vehicle front
1. Body ground E24 2. Engine ground F9 3. Engine ground F16
4. Body ground E15 BBIA0698E
PBIB3324E
Voltage: Approximately 5V
PBIB0080E
Continuity should exist.

EC-678< SERVICE INFOMATION >
[MR TYPE 1]
DTC P0117, P0118 ECT SENSOR
Refer to EC-678, " Component Inspection " .
OK or NG OK >> GO TO 5.
NG >> Replace engine coolant temperature sensor. 5.
CHECK INTERMITTENT INCIDENT
Refer to EC-626 .
>> INSPECTION END
Component Inspection INFOID:0000000004537141
ENGINE COOLANT TEMPERATURE SENSOR
1. Check resistance between engine coolant temperature sensor terminals 1 and 2 as shown in the figure.

2. If NG, replace engine coolant temperature sensor.
Removal and Installation INFOID:0000000004537142
ENGINE COOLANT TEMPERATURE SENSOR
Refer to EM-185 . PBIB2005E
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-684< SERVICE INFOMATION >
[MR TYPE 1]
DTC P0125 ECT SENSOR
DTC P0125 ECT SENSOR
Description INFOID:0000000004537151
NOTE:
If DTC P0125 is displayed with P0117 or P0118, fi rst perform the trouble diagnosis for DTC P0117 or
P0118. Refer to EC-674 .
COMPONENT DESCRIPTION
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 values 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:0000000004537152
This self-diagnosis ha one trip detection logic.
DTC Confirmation Procedure INFOID:0000000004537153
CAUTION:
Be careful not to overheat engine.
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.
2. Select “DATA MONITOR” mode with CONSULT-III.
3. Check that “COOLAN TEMP/S” is above 10 °C (50 °F). 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
P0125
0125 Insufficient engine cool-
ant temperature for
closed loop fuel control • Voltage sent to ECM from the sensor is not
practical, even when some time has passed
after starting the engine.
• Engine coolant temperature is insufficient for closed loop fuel control. • Harness or connectors
(High resistance in the circuit)
• Engine coolant temperature sensor
• Thermostat

DTC P0125 ECT SENSOR
EC-685
< SERVICE INFOMATION >
[MR TYPE 1] C
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If it is above 10
°C (50 °F), the test result will be OK.
If it is below 10 °C (50 °F), go to following step.
4. Start engine and run it for 65 minutes at idle speed. If “COOLAN TEMP/S” increases to more than 10 °C (50 °F) within 65 minutes, stop engine because
the test result will be OK.
5. Check DTC.
6. If DTC is detected, go to EC-685, " Diagnosis Procedure " .
WITH GST
Follow the procedure “WITH CONSULT-III” above.
Diagnosis Procedure INFOID:00000000045371541.
CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screw on the body.
Refer to EC-632, " Ground Inspection " .
OK or NG OK >> GO TO 2.
NG >> Repair or replace ground connections. 2.
CHECK ENGINE COOLANT TEMPERATURE SENSOR
Refer to EC-686, " Component Inspection " .
OK or NG OK >> GO TO 3.
NG >> Replace engine coolant temperature sensor. 3.
CHECK THERMOSTAT OPERATION
When the engine is cold [lower than 70 °C (158 °F)] condition, grasp lower radiator hose and confirm the engine
coolant does not flow.
OK or NG OK >> GO TO 4.
NG >> Repair or replace thermostat. Refer to CO-45 .
4.
CHECK INTERMITTENT INCIDENT
Refer to EC-626 .
Refer to EC-676, " Wiring Diagram " .
>> INSPECTION END :
Vehicle front
1. Body ground E24 2. Engine ground F9 3. Engine ground F16
4. Body ground E15 BBIA0698E