Infiniti F50. Manual - part 387

DTC P0112, P0113 IAT SENSOR

EC-189

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Component Inspection

EBS00LXY

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

EBS00LXZ

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-190

DTC P0117, P0118 ECT SENSOR

DTC P0117, P0118 ECT SENSOR

PFP:22630

Component Description

EBS00LY0

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 121
(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

EBS00LY1

These self-diagnoses have the one trip detection logic.

FAIL-SAFE MODE

When the malfunction is detected, the ECM enters fail-safe mode and the MIL lights up.

SEF594K

Engine coolant temperature

°

C (

°

F)

Voltage*

V

Resistance

k

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

P0117
0117

Engine coolant temperature 
sensor circuit low input

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

●

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

●

Engine coolant temperature sensor 

P0118
0118

Engine coolant temperature 
sensor circuit high input

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

Detected items

Engine operating condition in fail-safe mode

Engine coolant temper-

ature sensor circuit

Engine coolant temperature will be determined by ECM based on the time after turning ignition switch “ON” 
or “START”.
CONSULT-II displays the engine coolant temperature decided by ECM.

Condition

Engine coolant temperature decided 

(CONSULT-II display)

Just as ignition switch is turned ON or START

40

°

C (104

°

F)

More than approx. 4 minutes after ignition ON or 
START

80

°

C (176

°

F)

Except as shown above

40 - 80

°

C (104 - 176

°

F)

(Depends on the time)

When the fail-safe system for engine coolant temperature sensor is activated, the cooling fan operates while 
engine is running.

DTC P0117, P0118 ECT SENSOR

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DTC Confirmation Procedure

EBS00LY2

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.

 WITH CONSULT-II

1.

Turn ignition switch “ON”.

2.

Select “DATA MONITOR” mode with CONSULT-II.

3.

Wait at least 5 seconds.

4.

If DTC is detected, go to 

EC-193, "Diagnostic Procedure"

 .

 WITH GST

Follow the procedure “WITH CONSULT-II” above.

SEF058Y

EC-192

DTC P0117, P0118 ECT SENSOR

Wiring Diagram

EBS00LY3

TBWM0009E