How to test oil pressure switch wiring?

Post by **hausmeister** » 20 Apr 2025, 12:23

Hey guys

I assumed it would have 12v with key on, which it does not have. (I maybe broke the cable)
Any tips on how to test the single wire to the sensor/switch?

I was feeling masochistic and decided to install an aliexpress oil pressure gauge, with T adapter and so forth, That went okay, I have no skin on my arms left but it does not seem to leak.

But the stock oil pressure switch does not work any more. It has closed circuit to ground (engine off) I verified that this is the case, but the warning light does not come on. I had to extend the cable, and I think I did it right, but it is very hard to work down there. What can I measure the cable against to verify continuity/that it is ok? The plug also looks a bit suspect.

Bonus video of gauge, but the cable is only .5meters or so, so could not install it yet. At least it was cheap.

Post by **hausmeister** » 26 Apr 2025, 09:44

Well, I am still not sure how to test the wire, I tried a testlight , and that would glow when I tried it on 12v.

But, it is working again, the connector is a bit wonky, I reconnected it again and now it works. I also bought a pressure switch with a flat connector because I can't find the round plug, if it fails again I'll change it with that one.

Post by **hausmeister** » 26 Apr 2025, 09:52

Some pics of the pressure sensor + adapter I used.

Post by **abscate** » 26 Apr 2025, 19:16

The oil pressure switch is NC and is opened by oil pressure, so it should so continuity to ground with engine off, and open circuit with oil pressure of something like 0.25 bar