so I did some testing today. With the sensor unplugged, engine off and ignition on I have 32 mV on the blue signal wire V4 input. Sensor plugged in and the signal wire has 4V, with the engine off, looks like the sensor went bad.
4V in this sensor is the equivalent of 80 PSI and my car has a 3.5 bar FP regulator so the max I would ever see is about 50psi.
I even unplugged the fuel pump and cranked the engine a couple of times and I was still seeing 4V in the signal wire when plugged into the ECU with the engine off and ignition on.