P0111

P0111 IAT Sensor

Component Description

The intake air temperature sensor is built-into the mass air flow sensor (1). 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 rise in temperature.

[Reference data]









*: These data are reference values and are measured between ECM terminals 51 (Intake air temperature sensor) and 67 (Sensor ground).

On Board Diagnosis Logic






DTC Confirmation Procedure

1. INSPECTION START

Is it necessary to erase permanent DTC?
YES
GO TO 3.
NO
GO TO 2.

2. PERFORM COMPONENT FUNCTION CHECK

Perform component function check. Refer to "Component Function Check".

NOTE:
Use the component function check to check the overall function of the IAT sensor circuit. During this check, a 1st trip DTC might not be confirmed.

Is the inspection result normal?
YES
INSPECTION END
NO
Proceed to "Diagnosis Procedure".

3. PRECONDITIONING

If DTC CONFIRMATION PROCEDURE has been previously conducted, always perform the following procedure before conducting 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.
TESTING CONDITION:
- Before performing the following procedure, do not add fuel.
- Before performing the following procedure, check that fuel level is between 1/4 and 4/4.
- Before performing the following procedure, confirm that battery voltage is 11 V or more at idle.


GO TO 4.

4. PERFORM DTC CONFIRMATION PROCEDURE

1 Start engine and let it idle for 60 minutes.
2 Move the vehicle to a cool place.

NOTE:
Cool the vehicle in an environment of ambient air temperature between -10 °C (14 °F) and 35 °C (95 °F).

3 Turn ignition switch OFF and soak the vehicle for 12 hours.

CAUTION:
Never turn ignition switch ON during soaking.

NOTE:
The vehicle must be cooled with the food open.

4 Start engine and let it idle for 5 minutes or more.

CAUTION:
Never turn ignition switch OFF during idling.

5 Check 1st trip DTC.

Is 1st trip DTC detected?
YES
Proceed to "Diagnosis Procedure".
NO
INSPECTION END

Component Function Check

1. CHECK INTAKE AIR TEMPERATURE (IAT) SENSOR

1 Turn ignition switch OFF.
2 Disconnect mass air flow sensor harness connector.
3 Check resistance between mass air flow sensor terminals as follows.






Is the inspection result normal?
YES
GO TO 2.
NO
Proceed to "Diagnosis Procedure".

2. CHECK INTERMITTENT INCIDENT

Check intermittent incident. Refer to [Service Information for Electrical Incident: Intermittent Incident] Service Information for Electrical Incident: Intermittent Incident.

Is the inspection result normal?
YES
INSPECTION END
NO
Proceed to "Diagnosis Procedure".

Diagnosis Procedure

1. CHECK INTAKE AIR TEMPERATURE (IAT) SENSOR

Check intake air temperature sensor. Refer to "Component Inspection".

Is the inspection result normal?
YES
GO TO 2.
NO
Replace mass air flow sensor (with intake air temperature sensor). Refer to [Air Cleaner and Air Duct: Removal and Installation] Removal and Installation.

2. CHECK INTERMITTENT INCIDENT

Check intermittent incident. Refer to [Service Information for Electrical Incident: Intermittent Incident] Service Information for Electrical Incident: Intermittent Incident.


INSPECTION END

Component Inspection

1. CHECK INTAKE AIR TEMPERATURE (IAT) SENSOR

1 Turn ignition switch OFF.
2 Disconnect mass air flow sensor harness connector.
3 Check resistance between mass air flow sensor terminals as follows.






Is the inspection result normal?
YES
INSPECTION END
NO
Replace mass air flow sensor (with intake air temperature sensor). Refer to [Air Cleaner and Air Duct: Removal and Installation] Removal and Installation.