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Ol pressure switch

2005 Town and Country 3.8 FWD.

5 VOLT SUPPLY - PCM OUTPUT
The PCM supplies 5 volts to the following sensors:

  • A/C pressure transducer
  • Ambient Temperature sensor
  • Battery temperature
  • Camshaft Position Sensor (NGC)
  • Crankshaft Position Sensor (NGC)
  • Engine coolant temperature sensor
  • Inlet Air Temperature Sensor
  • Knock sensor
  • Linear EGR solenoid (if equipped)
  • Manifold absolute pressure sensor
  • Oil Pressure Switch
  • Throttle position sensor

This is from All data.
My oil light flickered. I checked pressure with mechanical gage, all is good. I replaced switch then light comes on stays on sometimes turns off. I started to check wiring integrity and in the process I discovered oil coming out of the electrical end of the new sensor. So the problem is resolved.

But I just have one question I’d like answered about something, because I like to learn things. From All data in PCM Description of operation it states that supply voltage to the oil pressure switch is 5 volts. When I checked voltage at the switch connector, unplugged, I got battery voltage. I believe everything is in working order, I am just wondering if anyone can educate me on why I am seeing battery voltage instead of 5 volts. I did not check voltage with connector hooked up, but it says supply voltage, which to me means voltage to sensor from PCM should be 5 volts.

Sorry, I had a brain fart. I can answer my own question. 5 volt referance is for a two wire sensor so that it has something to reference from. Mine is a one wire sensor, which is battery voltage on or off. Couldn’t delete post so I just responded to my question.

I owned a 2003 and 2004 Chrysler, both had bad oil pressure sending units and did my two grandaughters , 2004 and 2005. Only 1 of the 4 were leaking, The rest would randomly stay on after you started the car and not turn off until you shut it off but would work normally if you restarted it. Actual oil pressure in all 4 was good.

This is the second time I replaced one on this vehicle. This time I replaced it simply because the light flickered and pressure tested good. After I finally got a good one in it, light came back on. I cleaned the connector and pinched the connector tighter and it works fine now. Such a hassle for a 30 minute job.