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Barometric Pressure Sensor: Description and Operation

PURPOSE
The Barometric Pressure (BARO) sensor detects changes in atmospheric pressure. This information is transferred to the Powertrain Control Module (PCM) by an input signal. The PCM will adjust air/fuel ratio, A/C cutoff, idle speed, and purge control to compensate for the changing pressure.

OPERATION
The BARO sensor is a frequency generating device producing varying signals depending on the amount of barometric (atmospheric) pressure.