How does an oil pressure switch work?

[SilverRA23]

OK so this is probably mechanics 101, but can someone explain to me how an oil pressure switch works.

I have the oil pressure warning light coming on in my club car. Oil pressure gauge (electrically driven) shows 250kpa at idle but the light is on.

Replaced switch. Same result. Disconnecting switch, light stays on. Earthing the wire to the switch, the light stays on. So I wonder how the thing actually gets turned on and off?

I of course could have an oil pressure problem and thats why the light wont go away, but the gauge is reading fine, so I am trying to avoid pulling the motor out!

Any suggestions would be most appreciated as its starting to shit me

[STR8 2.8]

should be a short somewhere in the wire, causing it to stay on.
when the pressure is up, the switch will open the circuit and the light will go out.

[Draven]

^ ^ trace the wire, and look for where the insulation has corroded/worn through causing a short

[SilverRA23]

Thanks for your suggestions guys. Much appreciated!

[lexsmaz]

As the others have basically said, the oil pressure switch is an earth source for the light, if when you disconnect the switch & the light stays on it means you are getting another earth source to the light .. Problem is between the oil press dash light & the oil pressure switch .. Have a look over the wiring and at the worst it might be easier to run a new wire through ? ..