Nissan Frontier D22. Manual - part 414

DTC P0122, P0123 TP SENSOR

EC-759

[VG33E]

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Component Inspection

UBS00DH7

THROTTLE POSITION SENSOR

 With CONSULT-II

1.

Start engine and warm it up to normal operating temperature.

2.

Stop engine (ignition switch OFF).

3.

Turn ignition switch ON.

4.

Select “DATA MONITOR” mode with CONSULT-II.

5.

Check voltage of “THRTL POS SEN” under the following condi-
tions.
Voltage measurement must be made with throttle position
sensor installed in vehicle.

 With GST

1.

Start engine and warm it up to normal operating temperature.

2.

Stop engine (ignition switch OFF).

3.

Turn ignition switch ON.

4.

Check voltage between ECM terminal 23 (Throttle position sensor signal) and ground.
Voltage measurement must be made with throttle position sensor installed in vehicle.

Throttle valve conditions

THRTL POS SEN

Completely closed (a)

0.15 - 0.85V

Partially open

Between (a) and (b)

 Completely open (b)

3.5 - 4.7V

SEF719Y

Throttle valve conditions

Voltage [V]

Completely closed

0.15 - 0.85 (a)

Partially open

Between (a) and (b)

 Completely open

3.5 - 4.7 (b)

EC-760

[VG33E]

DTC P0125 ECT SENSOR

DTC P0125 ECT SENSOR

PFP:22630

Component Description

UBS00DH8

NOTE:
If DTC P0125 is displayed with P0117 or P0118, first perform the trouble diagnosis for DTC P0117 or
P0118. Refer to 

EC-738

 .

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 59
(Engine coolant temperature sensor) and ground.

CAUTION:

Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than the ECM terminals, such as the ground.

On Board Diagnosis Logic

UBS00DH9

DTC Confirmation Procedure

UBS00DHA

CAUTION:

Be careful not to overheat engine.

NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 5 seconds before conducting the next test.

 WITH CONSULT-II

1.

Turn ignition switch ON.

SEF594K

Engine coolant 

temperature

°C (°F)

Voltage*

(V)

Resistance

(k

Ω)

−10 (14)

4.4

9.2

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

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-761

[VG33E]

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2.

Select “DATA MONITOR” mode with CONSULT-II.

3.

Check that “COOLAN TEMP/S” is above 10

°C (50°F).

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.

If 1st trip DTC is detected, go to 

EC-761, "Diagnostic Procedure"

.

 WITH GST

Follow the procedure “WITH CONSULT-II”.

Diagnostic Procedure

UBS00DHB

1. 

CHECK ENGINE COOLANT TEMPERATURE SENSOR

Refer to 

EC-761, "Component Inspection"

 .

OK or NG

OK

>> GO TO 2.

 NG

>> Replace engine coolant temperature sensor.

2. 

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 3.

NG

>> Replace thermostat. Refer to 

CO-28, "THERMOSTAT"

 .

3. 

CHECK INTERMITTENT INCIDENT

Refer to 

EC-696, "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT"

 .

>> INSPECTION END.

Component Inspection

UBS00DHC

ENGINE COOLANT TEMPERATURE SENSOR

1.

Check resistance as shown in the figure.

<Reference data>

SEF174Y

SEF152P

EC-762

[VG33E]

DTC P0125 ECT SENSOR

2.

If NG, replace engine coolant temperature sensor.

Removal and Installation

UBS00DHD

ENGINE COOLANT TEMPERATURE SENSOR

Refer to 

EM-80, "OUTER COMPONENT PARTS"

 .

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