Air Flow Meter/Sensor: Description and Operation

AIR FLOW SENSOR (AFS): MASS AIR FLOW (MAF) SENSOR & INTAKE AIR TEMPERATURE SENSOR (ATS)

This hot film type Air Flow Sensor (AFS) is composed of a hot film sensor, housing and metering duct (hybrid sensor element). Mass air flow rate is measured because the change of the mass air flow rate causes a change in the amount of heat being transferred from the hot film probe surface to the air flow. The air flow sensor generates a pulse so it repeatedly opens and closes between the 5V voltage supplied from the ECM.

The intake air temperature sensor (ATS), located in the intake air hose, is a resistor-based sensor for detecting the intake air temperature. The intake air temperature information from the sensor helps the ECM provide the necessary fuel injection.