Mine's just started staying on all the time. It's done it for a couple of days. I thought the oil might be low (which it was, a bit), but now I've topped it up the light's still on. There doesn't appear to be anything wrong with the engine at all, and there are no oil leaks. So I'm guessing it's just the switch that's at fault?

I'm driving down to That London this evening, so I hope there's nothing drastic going on!

Maybe the wire or a wire had poped off?

Nah, it won't light up at all if the wire's disconnected. I'd go with the dicky switch theory.

Unless the wire is chafed and grounding somewhere.

The oil pressure switch connects to earth, so if the wire finds an earth elsewhere the light comes on.

Simple test - remove terminal from oil switch. If light stays on, it's a wiring fault. If light goes out, it's a faulty sensor.

Or worse...

Cheers chaps. It's obviously nothing much, as I've just returned from a 300 mile full-chat blast down the motorways to Windsor and back, and the car's running like a dream. The light didn't come on today at all anyway. I'll investigate wiring etc. at the weekend.

Ok, a 300-mile, full-chat blast is one way of testing your oil pressure...

Pleased it doesn't seem to be a serious problem

To be honest, having had a major oil leak when the oil pressure light wasn't connected, a 5 mile gentle potter to work would have been a fairly conclusive test..

Not my finest hour!

Yep, I just thought "it'll either get me there and back with no problem, or I'll have to call the recovery people".

It was only when I'd gone a way down the road that I realised I'd "done a Russ" and not got the recovery company's phone number on me...