Barometric Pressure Sensor: Description and Operation

PURPOSE
Fluctuations in air pressure cause changes in air density. The high altitude compensator detects and reports theses fluctuations to the ECM.

LOCATION
Built inside the ECM.

OPERATION
A small electrical signal is created when the piezo-crystal inside the unit is flexed by changing atmospheric pressure. The voltage is then processed by an amplifier circuit and converted to a voltage output the ECM understands.