Nissan Pathfinder (2008 year). Manual - part 311

EC-848, "Component Inspection"

OK or NG

>> GO TO 11.

>> GO TO 6.

REPLACE ACCELERATOR PEDAL ASSEMBLY

Replace the accelerator pedal assembly.

EC-497, "Accelerator Pedal Released Position Learning"

EC-497, "Idle Air Volume Learning"

>> INSPECTION END

CHECK THROTTLE POSITION SENSOR 2 GROUND CIRCUIT FOR OPEN AND SHORT

Turn ignition switch OFF.

Disconnect ECM harness connector.

Check harness continuity between electric throttle control actuator terminal 4 and ECM terminal 66.
Refer to Wiring Diagram.

Also check harness for short to ground and short to power.

OK or NG

>> GO TO 8.

>> Repair open circuit or short to ground or short to power in harness or connectors.

CHECK THROTTLE POSITION SENSOR 2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

Check harness continuity between ECM terminal 69 and electric throttle control actuator terminal 3.
Refer to Wiring Diagram.

Also check harness for short to ground and short to power.

OK or NG

>> GO TO 9.

>> Repair open circuit or short to ground or short to power in harness or connectors.

CHECK THROTTLE POSITION SENSOR

EC-606, "Component Inspection"

OK or NG

>> GO TO 11.

>> GO TO 10.

10.

REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR

Replace the electric throttle control actuator.

EC-497, "Idle Air Volume Learning"

>> INSPECTION END

11.

CHECK INTERMITTENT INCIDENT

GI-51, "Intermittent Incident"

Continuity should exist.

EC-606

< COMPONENT DIAGNOSIS >

[VK56DE]

P0122, P0123 TP SENSOR

>> INSPECTION END

Component Inspection

INFOID:0000000001537679

THROTTLE POSITION SENSOR

Reconnect all harness connectors disconnected.

Turn ignition switch ON

Set selector lever to D position.

Check voltage between ECM terminals 50 (TP sensor 1 signal),
69 (TP sensor 2 signal) and ground under the following condi-
tions.

If NG, replace electric throttle control actuator and go to the next
step.

EC-497, "Idle Air Volume Learning"

Terminal

Accelerator pedal

Voltage

50
(Throttle position sensor 1)

Fully released

More than 0.36V

Fully depressed

Less than 4.75V

69
(Throttle position sensor 2)

Fully released

Less than 4.75V

Fully depressed

More than 0.36V

PBIB1530E

P0125 ECT SENSOR

EC-607

< COMPONENT DIAGNOSIS >

[VK56DE]

P0125 ECT SENSOR

Component Description

INFOID:0000000001537680

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

EC-599

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>

*: This data is reference value and is measured between ECM terminal 73 (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 ECM terminals, such as the ground.

On Board Diagnosis Logic

INFOID:0000000001537681

DTC Confirmation Procedure

INFOID:0000000001537682

CAUTION:

Be careful not to overheat engine.
NOTE:
If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct-
ing the next step.
1.

Turn ignition switch OFF and wait at least 10 seconds.

Turn ignition switch ON.

Turn ignition switch OFF and wait at least 10 seconds.

WITH CONSULT-III

Turn ignition switch ON.

Select “DATA MONITOR” mode with CONSULT-III.

Check that “COOLAN TEMP/S” is above 31

C (88

F).

SEF594K

Engine coolant

temperature

C (

Voltage*

Resistance

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 coolant
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

EC-608

< COMPONENT DIAGNOSIS >

[VK56DE]

P0125 ECT SENSOR

If it is above 31

C (88

F), the test result will be OK.

If it is below 31

C (88

F), go to following step.

Start engine and run it for 65 minutes at idle speed.
If “COOLAN TEMP/S” increases to more than 31

C (88

F) within 65 minutes, stop engine because

the test result will be OK.

Check 1st trip DTC.

If 1st trip DTC is detected, go to

EC-608, "Diagnosis Procedure"

WITH GST

Follow the procedure “WITH CONSULT-III” above.

Diagnosis Procedure

INFOID:0000000001537683

CHECK GROUND CONNECTIONS

Turn ignition switch OFF.

Loosen and retighten three ground screws on the body.
Refer to

EC-565, "Ground Inspection"

OK or NG

>> GO TO 2.

>> Repair or replace ground connections.

CHECK ENGINE COOLANT TEMPERATURE SENSOR

EC-608, "Component Inspection"

OK or NG

>> GO TO 3.

>> Replace engine coolant temperature sensor.

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

>> GO TO 4.

>> Repair or replace thermostat. Refer to

CO-51, "Removal and Installation"

CHECK INTERMITTENT INCIDENT

GI-51, "Intermittent Incident"

For Wiring Diagram, refer to

EC-897, "Wiring Diagram - ENGINE CONTROL SYSTEM -"

>> INSPECTION END

Component Inspection

INFOID:0000000001537684

ENGINE COOLANT TEMPERATURE SENSOR

BBIA0539E

P0125 ECT SENSOR

EC-609

< COMPONENT DIAGNOSIS >

[VK56DE]

Check resistance between engine coolant temperature sensor
terminals 1 and 2 as shown in the figure.

<Reference data>

If NG, replace engine coolant temperature sensor.

PBIB2005E

Engine coolant temperature

C (

Resistance

Ω

20 (68)

2.1 - 2.9

50 (122)

0.68 - 1.00

90 (194)

0.236 - 0.260

SEF012P

EC-610

< COMPONENT DIAGNOSIS >

[VK56DE]

P0127 IAT SENSOR

P0127 IAT SENSOR

Component Description

INFOID:0000000001537685

The intake air temperature sensor is built into mass air flow sensor.
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.

<Reference data>

*: This data is reference value and is measured between ECM terminal 34 (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 Diagnosis Logic

INFOID:0000000001537686

DTC Confirmation Procedure

INFOID:0000000001537687

NOTE:
If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct-
ing the next step.
1.

Turn ignition switch OFF and wait at least 10 seconds.

Turn ignition switch ON.

Turn ignition switch OFF and wait at least 10 seconds.

CAUTION:

Always drive vehicle at a safe speed.
TESTING CONDITION:
This test may be conducted with the drive wheels lifted in the shop or by driving the vehicle. If a road
test is expected to be easier, it is unnecessary to lift the vehicle.

WITH CONSULT-III

Wait until engine coolant temperature is less than 90

C (194

Turn ignition switch ON.

Select “DATA MONITOR” mode with CONSULT-III.

Check the engine coolant temperature.

BBIA0355E

Intake air temperature

C (

Voltage*

Resistance

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

P0127
0127

Intake air temperature
too high

Rationally incorrect voltage from the sensor is
sent to ECM, compared with the voltage signal
from engine coolant temperature sensor.

• Harness or connectors

(The sensor circuit is open or shorted)

• Intake air temperature sensor

P0127 IAT SENSOR

EC-611

< COMPONENT DIAGNOSIS >

[VK56DE]

If the engine coolant temperature is not less than 90

C (194

F), turn ignition switch OFF and cool down

engine.
• Perform the following steps before engine coolant temperature is above 90

C (194

F).

Turn ignition switch ON.

Select “DATA MONITOR” mode with CONSULT-III.

Start engine.

Hold vehicle speed at more than 70 km/h (43 MPH) for 100 consecutive seconds.

Check 1st trip DTC.

If 1st trip DTC is detected, go to

EC-611, "Diagnosis Procedure"

WITH GST

Follow the procedure “WITH CONSULT-III” above.

Diagnosis Procedure

INFOID:0000000001537688

CHECK GROUND CONNECTIONS

Turn ignition switch OFF.

Loosen and retighten three ground screws on the body.
Refer to

EC-565, "Ground Inspection"

OK or NG

>> GO TO 2.

>> Repair or replace ground connections.

CHECK INTAKE AIR TEMPERATURE SENSOR

EC-611, "Component Inspection"

OK or NG

>> GO TO 3.

>> Replace mass air flow sensor (with intake air temperature sensor).

CHECK INTERMITTENT INCIDENT