Diagnostic Aids

WARNING: This page is about a different car, the 2016 Cadillac ATS. However, it is still accessible from the selected car via links, so may be relevant.

The IAT Sensor 1 and IAT Sensor 2 are integrated with the multifunction intake air sensor.
With the ignition ON, engine OFF and cold; properly functioning IAT sensors 1 and 2 will cause the scan tool IAT Sensor 1 and 2 parameters to increase. This is due to the heat that is generated by the multifunction intake air sensor internal heating elements.
The humidity sensor and the IAT sensor 2 signals are sent to the ECM on the same circuit. If the IAT Sensor 2 parameters display the values: 10 Hz; -40°C (-40°F), and there are also Humidity Sensor DTCs, check for a circuit fault.