Oil pressure light

Probably one for JohnC as I know the oil pressure circuit was something he'd investigated before, but my oil pressure light on the dash has stopped working. Replaced the bulb, but I still don't see the indicator light up when the ignition is primed before starting the car. I think that sensor (for the light) is still available, but prior to that, what's the best option to check?

Thanks.

Thanks for the PM John. All now sorted.

Earthed the wire to the sump with my handy crocodile clip lead and yep light came on. Managed to then gently tease the connector from the pressure sender (flat bladed screwdriver, twist, wiggle and repeat) and it was clear it was heavily corroded. Cleaned it up with some Emery cloth and good squirt of contact cleaner. All now good.

Changed the oil and filter at the same time and I think we're done.