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Re: VW T25 1.9l oil pressure switch

Posted: 01 Jul 2019, 05:22
by kevtherev
937carrera wrote:
937carrera wrote: The switch is "normally closed" which means if you were to do a continuity test with a meter between the spade and the threads you should see zero ohms.

What you called a dead short is a closed switch or zero ohms. That's normal / correct.

If the replacement is open circuit then it's faulty / the wrong one
Back to the circuitry then.
Wait, has the pressure been checked mechanically?
Just so you know there's no long term damage being done.
I fitted a mechanical gauge, no need for lights now.

Re: VW T25 1.9l oil pressure switch

Posted: 01 Jul 2019, 06:54
by 937carrera
kevtherev wrote: Back to the circuitry then.
Wait, has the pressure been checked mechanically?
Just so you know there's no long term damage being done.
I fitted a mechanical gauge, no need for lights now.

Not necessarily........ the existing switch is fine in the resting position, but we do not know if the switch opens when it should at 0.25 bar.

I did suggest that the OP check the wiring independently, he seems to want to use a meter to test it rather than simply use the existing van wiring and earthing /removing the spade to correct operation. It's only 2 minutes to test that way.

It's a good idea to measure the oil pressure with a gauge. Of course he'll need the threads repairing first, and it may well be best to test the pressure with existing oil before doing an oil change and retesting. On the other hand, if the light goes out when the new switch is fitted, then it's happy days :)

Re: VW T25 1.9l oil pressure switch

Posted: 01 Jul 2019, 11:37
by Phil1080
The Vans booked In to a garage on Thursday so will see what they say. I'll check the switch again tonight. I used the other coloured ones for comparison but they may be differently setup. I.e nc vs no. Will check again tonight. The one fit originally, I'm sure was closed o back to square one if thats the way the blue one is. Dam. I'll see what the garage says. They've worked alot on the t25s so should be able to find the issue pretty quickly.

Re: VW T25 1.9l oil pressure switch

Posted: 01 Jul 2019, 11:46
by Phil1080
Yeah so apologies with my amazing terminology and confusion. the original I just had confirmed. It is functioning as normally closed. Dam.