Infiniti F50. Manual - part 392

DTC P0127 IAT SENSOR

EC-209

C

D

E

F

G

H

I

J

K

L

M

A

EC

Component Inspection

EBS00LYR

INTAKE AIR TEMPERATURE SENSOR

1.

Check resistance between intake air temperature sensor termi-
nals 3 and 5 under the following conditions.

<Reference data>

2.

If NG, replace mass air flow sensor (with intake air temperature
sensor).

Removal and Installation

EBS00LYS

MASS AIR FLOW SENSOR

Refer to 

EM-15, "AIR CLEANER AND AIR DUCT"

 .

SEC266C

Intake air temperature 

°

C (

°

F)

Resistance k

Ω

25 (77)

1.9 - 2.1

SEF012P

EC-210

DTC P0128 THERMOSTAT FUNCTION

DTC P0128 THERMOSTAT FUNCTION

PFP:21200

On Board Diagnosis Logic

EBS00LYT

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

EBS00LYU

NOTE:
If “DTC Confirmation Procedure” has been previously conducted, always turn ignition switch “OFF” and wait at
least 10 seconds before conducting the next test.
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 60

°

C (140

°

F).

 WITH CONSULT-II

1.

Replace thermostat with new one. Refer to 

CO-24, "THERMOSTAT AND WATER CONTROL VALVE"

 .

Use only a genuine NISSAN thermostat as a replacement. If an incorrect thermostat is used, the MIL may
come on.

2.

Turn ignition switch “ON”.

3.

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

4.

Check that the “COOLAN TEMP/S” is above 60

°

C (140

°

F).

If it is below 60

°

C (140

°

F), go to following step.

If it is above 60

°

C (140

°

F), stop engine and cool down the

engine to less than 60

°

C (140

°

F), then retry from step 1.

5.

Drive vehicle for 10 consecutive minutes under the following
conditions.

If 1st trip DTC is detected, go to 

EC-210, "Diagnostic Procedure"

 .

 WITH GST

1.

Follow the procedure “WITH CONSULT-II” above.

Diagnostic Procedure

EBS00LYV

1. 

CHECK ENGINE COOLANT TEMPERATURE SENSOR

Refer to 

EC-211, "Component Inspection"

 .

OK or NG

OK

>> INSPECTION END

NG

>> Replace engine coolant temperature sensor.

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

80 - 120 km/h (50 - 75 MPH)

PBIB1917E

DTC P0128 THERMOSTAT FUNCTION

EC-211

C

D

E

F

G

H

I

J

K

L

M

A

EC

Component Inspection

EBS00LYW

ENGINE COOLANT TEMPERATURE SENSOR

Check resistance as shown in the figure.

<Reference data>

If NG, replace engine coolant temperature sensor.

Removal and Installation

EBS00LYX

ENGINE COOLANT TEMPERATURE SENSOR

Refer to 

EM-61, "CYLINDER HEAD"

 .

PBIB2005E

Temperature 

°

C (

°

F)

Resistance k

Ω

20 (68)

2.1 - 2.9

50 (122)

0.68 - 1.0

90 (194)

0.236 - 0.260

SEF012P

EC-212

DTC P0132, P0152 HO2S1

DTC P0132, P0152 HO2S1

PFP:22690

Component Description

EBS00LYY

The heated oxygen sensor 1 is placed into the exhaust manifold. It
detects the amount of oxygen in the exhaust gas compared to the
outside air. The heated oxygen sensor 1 has a closed-end tube
made of ceramic zirconia. The zirconia generates voltage from
approximately 1V in richer conditions to 0V in leaner conditions. The
heated oxygen sensor 1 signal is sent to the ECM. The ECM adjusts
the injection pulse duration to achieve the ideal air-fuel ratio. The
ideal air-fuel ratio occurs near the radical change from 1 to 0V.

CONSULT-II Reference Value in Data Monitor Mode

EBS00LYZ

Specification data are reference values.

On Board Diagnosis Logic

EBS00LZ0

To judge the malfunction, the diagnosis checks that the heated oxy-
gen sensor 1 output is not inordinately high.

SEF463R

SEF288D

MONITOR ITEM

CONDITION

SPECIFICATION

HO2S1 (B1)
HO2S1 (B2)

●

Engine: After warming up

Maintaining engine speed at 2,000 rpm

0 - 0.3V 

←→

 Approx. 0.6 - 1.0V

HO2S1 MNTR (B1)
HO2S1 MNTR (B2)

●

Engine: After warming up

Maintaining engine speed at 2,000 rpm

LEAN 

←→

 RICH

Changes more than 5 times during 
10 seconds.

SEF301UA

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P0132
0132
(Bank 1)

Heated oxygen sensor 1 
circuit high voltage

An excessively high voltage from the sensor is 
sent to ECM.

●

Harness or connectors
(The sensor circuit is open or shorted)

●

Heated oxygen sensor 1

P0152
0152
(Bank 2)