Circuit/System Description

The barometric pressure (BARO) sensor is a transducer that varies resistance according to changes in altitude and atmospheric conditions. This gives the control module an indication the current of barometric pressure. The control module uses this information to calculate fuel delivery. The BARO sensor has a 5-volt reference circuit, a low reference circuit, and a signal circuit. The control module supplies 5 volts to the BARO sensor on a 5-volt reference circuit, and provides a ground on a low reference circuit. The BARO sensor provides a voltage signal to the control module on a signal circuit relative to the pressure changes. The control module compares the BARO sensor to the manifold absolute pressure (MAP) sensor in order to monitor the BARO sensor operation. If the difference between the two sensors is more than a predetermined amount, DTC P0069 sets.