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 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 5 V voltage supplied from the powertrain control module.