Circuit Operation

5 volts power is supplied to the barometric pressure sensor power terminal (terminal 1) from the ECM (terminal 81 - M/T) or PCM (terminal 46 - A/T). The ground terminal (terminal 5) is grounded with ECM (terminal 40 - M/T) or PCM (terminal 16 - A/T).
A voltage that is proportional to the atmospheric pressure is sent to the ECM (terminal 85 - M/T) or PCM (terminal 55 - A/T) from the barometric pressure sensor output terminal (terminal 2).