Gear is down, flaps 30, spoilers armed but I get the yellow master caution button illuminates on final approach. If I press recall nothing comes up. No vref set though, will that trigger the caution?FRED

"Off schedule descent" or some similar message? I see that sometimes when I'm just shooting TO's & landings; the message is illuminated on the overhead and the master light goes on.

That might be it. Saw it on the overgead once and yes, happens when I do circuits.

Check the FO side warning box.