Circuit Operation

A 5 volts current is supplied to the barometric pressure sensor power terminal (terminal No. 1) from the ECM (terminal No. 81 - M/T) or PCM (terminal No. 46 - A/T). The ground terminal (terminal No. 5) is grounded with ECM (terminal No. 40 - M/T) or PCM (terminal No. 16 - A/T).
A voltage that is proportional to the atmospheric pressure is sent to the ECM (terminal No. 85 - M/T) or PCM (terminal No. 55 - A/T) from the barometric pressure sensor output terminal (terminal No. 2).