Nissan Frontier D40. Manual - part 476

P0127 IAT SENSOR

EC-595

< COMPONENT DIAGNOSIS >

[VQ40DE]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

SEF012P

EC-596

< COMPONENT DIAGNOSIS >

[VQ40DE]

P0128 THERMOSTAT FUNCTION

P0128 THERMOSTAT FUNCTION

On Board Diagnosis Logic

INFOID:0000000005273566

NOTE:
If DTC P0128 is displayed with DTC P0300, P0301, P0302, P0303, P0304, P0305 or P0306, first perform
the trouble diagnosis for DTC P0300, P0301, P0302, P0303, P0304, P0305, P0306. Refer to 

EC-657,

"DTC Confirmation Procedure"

.

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 being stuck open.

DTC Confirmation Procedure

INFOID:0000000005273567

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

Turn ignition switch OFF and wait at least 10 seconds.

2.

Turn ignition switch ON.

3.

Turn ignition switch OFF and wait at least 10 seconds.

 WITH CONSULT-III

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 52

°

C (126

°

F).

• Before performing the following procedure, do not add fuel.
1.

Turn A/C switch OFF.

2.

Turn blower fan switch OFF.

3.

Turn ignition switch ON.

4.

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

5.

Check the indication of “COOLAN TEMP/S”.
If it is below 52

°

C (126

°

F), go to following step.

If it is above 52

°

C (126

°

F), cool down the engine to less than 52

°

C (126

°

F). Then go to next steps.

6.

Start engine and wait at idle for at least 10 minutes under the following conditions.

CAUTION:

Always drive vehicle at a safe speed.
NOTE:
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.

7.

Check 1st trip DTC.

8.

If 1st trip DTC is detected, go to 

EC-596, "Diagnosis Procedure"

.

 WITH GST

Follow the procedure “WITH CONSULT-III” above.

Diagnosis Procedure

INFOID:0000000005273568

1.

CHECK ENGINE COOLANT TEMPERATURE SENSOR

Refer to 

EC-597, "Component Inspection"

.

OK or NG

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

VHCL SPEED SE

More than  56 km/h (35MPH)

P0128 THERMOSTAT FUNCTION

EC-597

< COMPONENT DIAGNOSIS >

[VQ40DE]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

OK

>> GO TO 2.

NG

>> Replace engine coolant temperature sensor.

2.

CHECK THERMOSTAT

Refer to 

CO-54, "Removal and Installation"

.

OK or NG

OK

>> INSPECTION END

NG

>> Replace thermostat.

Component Inspection

INFOID:0000000005273569

ENGINE COOLANT TEMPERATURE SENSOR

1.

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

<Reference data>

2.

If NG, replace engine coolant temperature sensor.

PBIB2005E

Engine coolant 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-598

< COMPONENT DIAGNOSIS >

[VQ40DE]

P0130, P0150 A/F SENSOR 1

P0130, P0150 A/F SENSOR 1

Component Description

INFOID:0000000005273570

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

°

C

(1,472

°

F).

On Board Diagnosis Logic

INFOID:0000000005273571

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

DTC Confirmation Procedure

INFOID:0000000005273572

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.

2.

Turn ignition switch ON.

3.

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

1.

Start engine and warm it up to normal operating temperature.

2.

Let engine idle for 2 minutes.

3.

Check 1st trip DTC.

4.

If 1st trip DTC is detected, go to 

EC-599, "Diagnosis Procedure"

.

PBIB3353E

PBIB3354E

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible Cause

P0130
0130
(Bank 1)

Air fuel ratio (A/F) sensor 1 
circuit

A)

The A/F signal computed by ECM from the A/F 
sensor 1 signal is constantly in a 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)

B)

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