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 34 (Intake air temperature sensor) and 67 (Sensor ground).

On Board Diagnosis Logic






DTC Confirmation Procedure

1. 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".

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.