A power voltage of 5 V is applied to the rail pressure sensor power terminal (terminal No. 1) from the engine-ECU (terminal No. 70) and earthed to the engine-ECU (terminal No. 88) from the rail pressure sensor (terminal No. 3).
The sensor signal is inputted to the engine-ECU (terminal No. 64) from the rail pressure sensor output terminal (terminal No. 2).
The rail pressure sensor converts the rail pressure into a voltage signal and inputs the signal to the engine-ECU.
In response to the signal, the engine-ECU corrects the fuel injection quantity.
Battery positive voltage is 8 – 16 V
2 seconds later after the ignition switch has been in “ON” position or the engine has started up.
The rail pressure sensor output voltage is 4.85 V or more for 0.5 second.
Failed rail pressure sensor
Open circuit in rail pressure sensor circuit or loose connector contact