Oil sensor problem?

While I was driving my A8 to the gear box rebuilding firm, on the motorway i got a yellow oil can light + a text under it "SENSOR" on the dash.

Any idea what is this? The sensor doesn't work?

How to fix? (like doing the gear box rebuild wouldn't be enough for this month :-) )

Thanks for your help

[Duffy]

There a oil level sensor bolted onto the bottom of the sump, I've replaced mine twice for exactly the same fault.
It's a couple of bolts and a connector, and is more easily done during an oil change.

Thanks for the info! Have to check that and get it changed