I'm going to revive the oil pressure light in my '66 Toronado (had to have a gauge). What confuses me is that the pressure switch that I have is not normally closed (no continuity between connector and switch body with engine off). I was under the impression that these lights had the ground switched by the pressure switch, so the switch was closed with no pressure and opened over a certain pressure. Am I over thinking it?
Thanks.

 

When the switch closes it completes the ground circuit and the light works. When the engine produces roughly 5psi oil pressure it opens the circuit turning the lamp out.

The low setting for on/off is why many folks use gauges as you want to know that there is low oil pressure long before 5 psi.

Good luck!!!

 

Thank you. Shouldn't I have continuity in the switch from terminal to body with no pressure?

 

jump the two wires in the oil pressure switch connector together. With the key on the light should light. If it does your switch is bad. If it doesn't light you are going to have to diagnose the open in the circuit. To answer your question, yes with the engine off you should have continuity across the Oil pressure switch.

 

Yes there should be continuity with 0 pressure.

 

It sounds like it's probably time to change to another switch.

 

Thanks guys.