Operation CHARM: Car repair manuals for everyone.
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Air Flow Meter/Sensor: Description and Operation




MASS AIR FLOW (MAF) SENSOR
This hot film type air flow sensor is composed of a hot film sensor, housing and metering duct (hybrid, sensor element). Mass airflow rate is measured because the change of the mass air flow rate causes 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 5 V voltage supplied from the powertrain control module.