Barometric Pressure Sensor: Description and Operation

Barometric Pressure Sensor:

PURPOSE
The Engine Control Module (ECM) uses the voltage signal to adjust the air-fuel ratio and ignition timing as altitude changes to improve driveability at high altitude.

OPERATION
- The ECM supplies a 5 Volt reference and a ground to the sensor.
- As the resistance of the sensor changes the voltage across the sensor varies. This voltage is read as barometric pressure by the ECM.