Content .. 310 311 312 313 ..

Nissan Pathfinder (2008 year). Manual - part 312

P0128 THERMOSTAT FUNCTION

EC-613

< COMPONENT DIAGNOSIS >

[VK56DE]

P0128 THERMOSTAT FUNCTION

On Board Diagnosis Logic

INFOID:0000000001537690

Engine coolant temperature has not risen enough to open the thermostat even though the engine has run long
enough.
This is due to a leak in the seal or the thermostat stuck open.

DTC Confirmation Procedure

INFOID:0000000001537691

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.

TESTING CONDITION:
• For best results, perform at ambient temperature of –10

C (14

F) or higher.

• For best results, perform at engine coolant temperature of –10

C (14

F) to 71

C (160

F).

• Before performing the following procedure, do not fill with the fuel.

WITH CONSULT-III

Turn A/C switch OFF.

Turn blower fan switch OFF.

Turn ignition switch ON.

Select “COOLAN TEMP/S” in “DATA MONITOR” mode with CONSULT-III.

Check the indication of “COOLAN TEMP/S”.
If it is below 71

C (160

F), go to following step.

If it is above 71

C (160

F), cool down the engine to less than 71

C (160

F), then go to next step.

Start engine.

Wait at idle for a least 30 minutes.
If “COOLAN TEMP/S” increases to more than 71

C (160

F) within 30 minutes, turn ignition switch

OFF because the test result will be OK.

Check 1st trip DTC.

If 1st trip DTC is detected, go to

EC-613, "Diagnosis Procedure"

WITH GST

Follow the procedure “WITH CONSULT-III” above.

Diagnosis Procedure

INFOID:0000000001537692

CHECK ENGINE COOLANT TEMPERATURE SENSOR

Refer to

EC-614, "Component Inspection"

OK or NG

>> GO TO 2.

>> Replace engine coolant temperature sensor.

CHECK THERMOSTAT

Check thermostat. Refer to

CO-51, "Removal and Installation"

OK or NG

>> INSPECTION END.

>> Replace thermostat.

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P0128
0128

Thermostat function

The engine coolant temperature does not
reach to specified temperature even though
the engine has run long enough.

• Thermostat
• Leakage from sealing portion of thermostat
• Engine coolant temperature sensor

EC-614

< COMPONENT DIAGNOSIS >

[VK56DE]

P0128 THERMOSTAT FUNCTION

Component Inspection

INFOID:0000000001537693

ENGINE COOLANT TEMPERATURE SENSOR

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

P0130, P0150 A/F SENSOR 1

EC-615

< COMPONENT DIAGNOSIS >

[VK56DE]

P0130, P0150 A/F SENSOR 1

Component Description

INFOID:0000000001537694

The air fuel ratio (A/F) sensor 1 is a planar one-cell limit current sen-
sor. The sensor element of the A/F sensor 1 is composed an elec-
trode layer, which transports ions. It has a heater in the element.
The sensor is capable of precise measurement = 1, but also in the
lean and rich range. Together with its control electronics, the sensor
outputs a clear, continuous signal throughout a wide range.
The exhaust gas components diffuse through the diffusion layer at
the sensor cell. An electrode layer is applied voltage, and this current
relative oxygen density in lean. Also this current relative hydrocar-
bon density in rich.
Therefore, the A/F sensor 1 is able to indicate air fuel ratio by this
electrode layer of current. In addition, a heater is integrated in the
sensor to ensure the required operating temperature of about 800

(1,472

F).

On Board Diagnosis Logic

INFOID:0000000001537695

To judge the malfunction, the diagnosis checks that the A/F signal computed by ECM from the A/F sensor 1
signal fluctuates according to fuel feedback control.

DTC Confirmation Procedure

INFOID:0000000001537696

Perform PROCEDURE FOR MALFUNCTION A first.
If the DTC cannot be confirmed, perform PROCEDURE FOR MALFUNCTION B.
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.

TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.

PROCEDURE FOR MALFUNCTION A

Start engine and warm it up to normal operating temperature.

Let engine idle for 2 minutes.

Check 1st trip DTC.

If 1st trip DTC is detected, go to

EC-616, "Diagnosis Procedure"

PROCEDURE FOR MALFUNCTION B

PBIB3353E

PBIB3354E

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible Cause

P0130
0130
(Bank 1)

Air fuel ratio (A/F) sensor 1
circuit

The A/F signal computed by ECM from the A/F
sensor 1 signal is constantly in the range other
than approx. 2.2V.

• Harness or connectors

(The A/F sensor 1 circuit is open
or shorted.)

• Air fuel ratio (A/F) sensor 1

P0150
0150
(Bank 2)

The A/F signal computed by ECM from the A/F
sensor 1 signal is constantly approx. 2.2V.

EC-616

< COMPONENT DIAGNOSIS >

[VK56DE]

P0130, P0150 A/F SENSOR 1

CAUTION:

Always drive vehicle at a safe speed.

With CONSULT-III

Start engine and warm it up to normal operating temperature.

Select “A/F SEN1 (B1)” or “A/F SEN1 (B2)” in “DATA MONITOR” mode with CONSULT-III.

Check “A/F SEN1 (B1)” or “A/F SEN1 (B2)” indication.
If the indication is constantly approx. 2.2V and does not fluctuates, go to

EC-616, "Diagnosis Procedure"

If the indication fluctuates around 2.2V, go to next step.

Select “A/F SEN1 (B1) P1276” (for DTC P0130) or “A/F SEN1 (B2) P1286” (for DTC P0150) of “A/F
SEN1” in “DTC WORK SUPPORT” mode with CONSULT-III.

Touch “START”.

When the following conditions are met, “TESTING” will be displayed on the CONSULT-III screen.

If “TESTING” is not displayed after 20 seconds, retry from step 2.

Release accelerator pedal fully.
NOTE:
Never apply brake during releasing the accelerator pedal.

Make sure that “TESTING” changes to “COMPLETED”.
If “TESTING” changed to “OUT OF CONDITION”, retry from step 6.

Make sure that “OK” is displayed after touching “SELF-DIAG RESULT”.
If “NG” is displayed, go to

EC-616, "Diagnosis Procedure"

Overall Function Check

INFOID:0000000001537697

PROCEDURE FOR MALFUNCTION B

Use this procedure to check the overall function of the A/F sensor 1 circuit. During this check, a 1st trip DTC
might not be confirmed.

With GST

Start engine and warm it up to normal operating temperature.

Drive the vehicle at a speed of 80 km/h (50 MPH) for a few minutes in the suitable gear position.

Set shift lever to D position, then release the accelerator pedal fully until the vehicle speed decreases to
50 km/h (30 MPH).
NOTE:
Never apply brake during releasing the accelerator pedal.

Repeat steps 2 and 3 for five times.

Stop the vehicle and turn ignition switch OFF.

Turn ignition switch ON.

Turn ignition switch OFF and wait at least 10 seconds.

Restart engine.

Repeat steps 2 and 3 for five times.

10. Stop the vehicle and connect GST to the vehicle.
11. Make sure that no 1st trip DTC is displayed.

If the 1st trip DTC is displayed, go to

EC-616, "Diagnosis Procedure"

Diagnosis Procedure

INFOID:0000000001537698

CHECK GROUND CONNECTIONS

Turn ignition switch OFF.

Loosen and retighten three ground screws on the body.

ENG SPEED

850 - 3,200 rpm

VHCL SPEED SE

More than 64 km/h (40 MPH)

B/FUEL SCHDL

1.0 - 8.0 msec

Shift lever

D position

P0130, P0150 A/F SENSOR 1

EC-617

< COMPONENT DIAGNOSIS >

[VK56DE]

Refer to

EC-565, "Ground Inspection"

OK or NG

>> GO TO 2.

>> Repair or replace ground connections.

CHECK AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY CIRCUIT

Disconnect A/F sensor 1 harness connector.

Turn ignition switch ON.

Check voltage between A/F sensor 1 terminal 4 and ground with
CONSULT-III or tester.

OK or NG

>> GO TO 4.

>> GO TO 3.

DETECT MALFUNCTIONING PART

Check the following.
• Harness connectors E2, F32
• IPDM E/R harness connector E119
• 15A fuse
• Harness for open or short between A/F sensor 1 and fuse

>> Repair or replace harness or connectors.

CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

Turn ignition switch OFF.

Disconnect ECM harness connector.

Check harness continuity between the following terminals. Refer to Wiring Diagram.

BBIA0539E

ALBIA0360ZZ

A/F sensor 1 (bank 2) harness connector

A/F sensor 1 (bank 2)

A/F sensor 1 (bank 1)

A/F sensor 1 (bank 1) harness connector

: Vehicle front

Voltage: Battery voltage

PBIB3308E

EC-618

< COMPONENT DIAGNOSIS >

[VK56DE]

P0130, P0150 A/F SENSOR 1

Check harness continuity between the following terminals and ground.
Refer to Wiring Diagram.

Also check harness for short to power.

OK or NG

>> GO TO 5.

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

CHECK INTERMITTENT INCIDENT

Perform

GI-51, "Intermittent Incident"

OK or NG

>> GO TO 6.

>> Repair or replace.

REPLACE AIR FUEL RATIO (A/F) SENSOR 1

Replace malfunctioning air fuel ratio (A/F) sensor 1.

CAUTION:

• Discard any A/F sensor which has been dropped from a height of more than 0.5 m (19.7 in) onto a

hard surface such as a concrete floor; use a new one.

• Before installing new A/F sensor, clean exhaust system threads using Oxygen Sensor Thread

Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.

>> INSPECTION END

A/F sensor 1 terminal

ECM terminal

Bank1

Bank 2

Continuity should exist.

Bank 1

Bank 2

A/F sensor 1 terminal

ECM terminal

A/F sensor 1 terminal

ECM terminal

Continuity should not exist.

P0131, P0151 A/F SENSOR 1

EC-619

< COMPONENT DIAGNOSIS >

[VK56DE]

P0131, P0151 A/F SENSOR 1

Component Description

INFOID:0000000001537699

(1,472

F).

On Board Diagnosis Logic

INFOID:0000000001537700

To judge the malfunction, the diagnosis checks that the A/F signal computed by ECM from the A/F sensor 1
signal is not inordinately low.

DTC Confirmation Procedure

INFOID:0000000001537701

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.

TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10.5V at idle.

WITH CONSULT-III

Start engine and warm it up to normal operating temperature.

Select “A/F SEN1 (B1)” or “A/F SEN1 (B2)” in “DATA MONITOR” mode with CONSULT-III.

Check “A/F SEN1 (B1)” or “A/F SEN1 (B2)” indication.
If the indication is constantly approx. 0V, go to

EC-620, "Diagnosis Procedure"

If the indication is not constantly approx. 0V, go to next step.

Turn ignition switch OFF and wait at least 10 seconds.

Turn ignition switch ON.

PBIB3353E

PBIB3354E

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible Cause

P0131
0131
(Bank 1)

Air fuel ratio (A/F) sensor 1
circuit low voltage

• The A/F signal computed by ECM from the A/

F sensor 1 signal is constantly approx. 0V.

• Harness or connectors

(The A/F sensor 1 circuit is open or
shorted.)

• Air fuel ratio (A/F) sensor 1

P0151
0151
(Bank 2)

EC-620

< COMPONENT DIAGNOSIS >

[VK56DE]

P0131, P0151 A/F SENSOR 1

Turn ignition switch OFF and wait at least 10 seconds.

Restart engine.

Drive and accelerate vehicle to more than 40 km/h (25 MPH) within 20 seconds after restarting engine.

Maintain the following conditions for about 20 consecutive seconds.

NOTE:
• Keep the accelerator pedal as steady as possible during the cruising.
• If this procedure is not completed within 1 minute after restarting engine at step 4, return to step

10. Check 1st trip DTC.
11. If 1st trip DTC is displayed, go to

EC-620, "Diagnosis Procedure"

WITH GST

Follow the procedure “WITH CONSULT-III” above.

Diagnosis Procedure

INFOID:0000000001537702

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 AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY CIRCUIT

Disconnect A/F sensor 1 harness connector.

Turn ignition switch ON.

ENG SPEED

1,000 - 3,200 rpm

VHCL SPEED SE

More than 40 km/h (25 MPH)

B/FUEL SCHDL

1.5 - 9.0 msec

Gear position

Suitable position

BBIA0539E

A/F sensor 1 (bank 2) harness connector 2.

A/F sensor 1 (bank 2)

A/F sensor 1 (bank 1)

A/F sensor 1 (bank 1) harness connector

: Vehicle front

ALBIA0360ZZ

Content .. 310 311 312 313 ..