DTC 0401

COMPONENT DESCRIPTION
The intake air temperature sensor is mounted to the air duct. The sensor detects intake air temperature and transmists 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 temperature rising.
This sensor is not used to control the engine system. It is used only for the on board diagnosis.


Intake air temperature °C (°F) / Voltage (V) / Resistance K Ohms
20 (68) / 3.5 / 2.1 - 2.9
80 (176) / 1.23 / 0.27 - 0.38






ON BOARD DIAGNOSIS LOGIC
Engine operating condition in fail-safe mode.The ECM controls on the assumption that the intake air temperature is 20°C (68°F).

DIAGNOSTIC TROUBLE CODE CONFIRMATION PROCEDURE
Procedure for Malfunction A
With CONSULT
(1) Turn ignition switch to the "ON" position.






(2) Select "DATA MONITOR" mode with CONSULT.
(3) Wait at least 5 seconds.

OR

With GST
(1) Turn ignition switch to the "ON" position and wait at least 5 seconds.
(2) Select MODE 7 with the GST.

OR

No Tools
(1) Turn the ignition switch to the "ON" position and wait at least 5 seconds.
(2) Turn the ignition switch to the "OFF" position, wait at least 7 seconds and then turn back to the "ON" position.
(3) Perform "Diagnostic Test Mode II (Self-diagnostic results)" with the ECM.

Procedure for Malfunction B
With CONSULT
(1) Lift up vehicle and open engine hood.
(2) Wait until engine coolant temperature is less than 90°C (194°F).
(a) Turn ignition switch "ON".
(b) Select "DATA MONITOR" mode with CONSULT.




(c) Check the engine coolant temperature.
(d) If the engine coolant temperature is not less than 90°C (194°F), turn ignition switch "OFF" and cool down engine.
- Perform the following steps before engine coolant temperature is above 90°C (194°F).
(3) Turn ignition switch "ON".
(4) Select "DATA MONITOR" mode with CONSULT:
(5) Start engine.
(6) Shift selector lever to "D" position.
(7) Hold vehicle speed at 7O to 8O km/h (43 to 50 MPH) for 2 minutes.

OR

(1) Lift up vehicle and open engine hood.
(2) Wait until engine coolant temperature is less than 90°C (194°F).
(a) Turn ignition switch "ON".
(b) Select MODE 1 with GST.




(c) Check the engine coolant temperature.
(d) If the engine coolant temperature is not less than 90°C (194°F), turn ignition switch "OFF" and cool down engine.
- Perform the following steps before engine coolant temperature is above 90°C (194°F).
(3) Start engine.
(4) Shift selector lever to "D" position.
(5) Hold vehicle speed at 70 to 80 km/h (43 to 50 MPH) for 2 minutes.
(6) Select MODE 7 with GST.

OR

NO TOOLS
(1) Lift up vehicle and open engine hood.
(2) Wait until engine coolant temperature is less than 90°C (194°F).
(a) Turn ignition switch "ON".




(b) Check voltage between ECM terminal (51) and ground.

Voltage: More than 1.0 (V)

(c) If the voltage is not more than 1.0 (V), turn ignition switch "OFF" and cool down engine.
- Perform the following steps before the voltage is below 1.0V.
(3) Start engine.
(4) Shift selector lever to "D" position.
(5) Hold vehicle speed at 70 to 80 km/h (43 to 50 MPH) for 2 minutes.
(6) Turn ignition switch "OFF", wait at least 7 seconds and then turn "ON".
(7) Perform "Diagnostic Test Mode II (Self-diagnostic results)" with ECM.

EC-IATS-01 Intake Air Temperature Sensor (DTC P0110):

Wiring Diagram






Diagnostic Procedure

Component Inspection
Intake Air Temperature Sensor






Check resistance as shown.







Intake air temperature, °C (°F) / Resistance, K Ohms
20 (68) / 2.1 - 2.9
80 (176) / 0.27 - 0.38

If NG, replace the intake air temperature sensor.