Circuit Description
WARNING: This page is about a different car, the 2010 Chevrolet Cobalt. However, it is still accessible from the selected car via links, so may be relevant.
The barometric pressure (BARO) sensor is integrated within the engine control module (ECM). The BARO sensor voltage signal is converted by the ECM for display on the scan tool as the BARO Sensor kPa parameter. The BARO sensor signal varies, according to changes in altitude and atmospheric conditions. This gives the ECM an indication of the current barometric pressure. The ECM uses this information for numerous internal calculations. The ECM monitors the BARO sensor signal for voltages/pressures that are not within a normal range. The ECM also monitors the stability of the BARO sensor signal by comparing successive samples.