Nissan Maxima Service and Repair Manual: P0111 IAT sensor

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 50 (Intake air temperature sensor) and 56 (Sensor ground).

DTC Logic

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.INSPECTION START

2.PERFORM COMPONENT FUNCTION CHECK

Perform component function check. Refer to EC-196, "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.

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.

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 −10C (14F) and 35C (95F).
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.

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.

2.CHECK INTERMITTENT INCIDENT

Check intermittent incident.

Diagnosis Procedure

1.CHECK INTAKE AIR TEMPERATURE (IAT) SENSOR

Check intake air temperature sensor.

2.CHECK INTERMITTENT INCIDENT

Check intermittent incident.

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.