Sensor PWM Circuit

The FRT sensor information is required by the PCM for fuel trim adjustment. The FTP and FTT sensors information is required by the PCM for fuel gage operation. The PCM does not have the ability to supply and monitor the FRT, FTP and FTT sensors. The FICM performs this task by supplying the sensors a 5-volt reference, low reference and signal circuit. The signal voltage of the sensors are converted into a PWM signal. The PWM signal is sent to the PCM through a dedicated circuit. The PCM converts the PWM signal into pressure and temperature values.