2013 Ford Fiesta WZ st intermittent engine light

[Bourne]

HI All
I am interested in purchasing a Fiesta ST WZ. I have been advised by the seller that the vehicle has an intermittent engine light that flashes. The vehicle drives fine with no performance loss.
Can anyone please advise as to what the potential issue/s might be.
Would be happy to get it repaired if its a fairly easy fix.

Help would be greatly appreciated.
Thank you