Monitor Description
WARNING: This page is about a different car, the 2007 Lexus GS 430. However, it is still accessible from the selected car via links, so may be relevant.
The ECM monitors the sensor voltage and uses this value to calculate the intake air temperature. When the sensor output voltage deviates from the normal operating range, the ECM interprets this as a fault in the IAT sensor and sets a DTC.
Example:
When the ATF temperature is -40°C (-40°F) or more than 140°C (284°F) and if either condition continues for 0.5 seconds or more, the ECM will set a DTC.
This monitor runs 0.5 seconds after the engine switch is turned on (IG).