The Nissan Path

This morning when I started my pathy a display came on (replacing the odometer reading saying "lo oil".
I stopped and checked oil level, all OK. Drove on and it went off withing 1km.
What could this be? Does it come on from oil level or oil pressure?
This is on a 2.5 diesel engine

seems to indicate a faulty sensor or switch. but since this is a 2.5 diesel that we do no get in the US. i'm not certain