Should I keep the pressure sensor plugged in and tucked away somewhere? With it disconnected my computer is getting readings somehow and periodically passing the code for pressure switch, I assume it’* playing with the 5v if it’* doing that

What vehicle are you working on?

99 park avenue ultra, my bad I forgot that they didn’t all have the same v5 compressor or ac controls every year.

Here’* the diagram. I actually had a nick in the black wire which looks like the.. power signal? Idk how to read diagrams well. 5 volt gray is the reference circuit that if it gets pulled low then all 5 volt circuits are pulled low as they come from a shared piece on the pcm board

Here’* the diagram. I actually had a nick in the black wire which looks like the.. power signal? Idk how to read diagrams well. 5 volt gray is the reference circuit that if it gets pulled low then all 5 volt circuits are pulled low as they come from a shared piece on the pcm board


This is connector. My scan tool freeze frame indicates a proper pressure periodically is read when it tests but I never have this connected

I’m thinking voltage is shorting go the return? Or maybe the reference is, which without a sensor to resist would pull it low?

Sensor unplugged means it'* open. Open don't pull voltage down. That happens with current flow as in a short. What code is it setting?

uh I forget the p number but it’* sensor out of self test range and the freeze frame and fail records will have a proper voltage and reading on the “sensor” which was wrapped in vinyl and kept from touching anything. But the ac clutch connector was near by. You think it’* possible the ac clutch relay sending current with no proper pathway could find a conductive branch to the sensor and theoretically have a chance to give or propert read, pass the code test, and eventually fail again(code was passed and failed)
I was gonna check the schematic for ac clutch relay and make sure nothing else needs it. If not , I see no reason to leave it in

Of coarse it'* out of range. It'* not even hooked up. Either live with it or fix it.

again, without a sensor it’* getting live readings

My Olds Toronado does the same thing. I have the pressure sensor unhooked because my compressor is bad and intermittently the dash read out will say low on refrigerant or very low. Sometimes it does it and sometimes it doesn't. very random. who knows. If I hook it up it keeps putting that message up constantly, that'* why I unhooked it.