V35 Oil pressure light

Click - no start - now fixed, so a new problem has manifested itself.

The oil light no longer illuminates (at all). I did a recent oil and filter change so I know there’s plenty of the correct oil and the engine is running fine.

However, I have tested the oil pressure switch for resistance (using the 200 ohm setting on my multi-meter) and I’m getting a reading of “1”, so it’s open circuit and likely needs replacing. More concerning, the feed wire (blue/black) was showing 2.3 volts, whereas I was expecting 12! The usual bodge to test the oil light is to earth the feed wire with the ignition on at which point it should illuminate - it doesn’t, but at 2.3 volts I’m not surprised.

So I suspect a corroded or frayed wire somewhere under the petrol tank or in the steering head area.

Anyone got any experience of this fault and its resolution?


A fastest one? Switch to LEDs, they go on much quicker, even on poor voltage. But OK, I know, not that easy to find LED in the shape of our idiot lights. If you got wiring diagram, see where connectors are hidden on way from actual bulb to feed - as long as I remember plenty of dash bulbs are fed from common +ve, so I’d expect poor feedback from neutral and charging too.
Also the under-the-tank 12- or 15-pin blocks are known to be very Italian. look into them. And then, please report.