dL_ST, have had the same exact thing happen to me in my 15 Fiesta ST. Wrench light came on at 10,250 miles, has been driving normal but the reset didn't work with me either. took it in to the dealership no codes came up, they told me it's because I needed an oil change. However, my oil was changed at 7,600 miles so i highly doubt that's the case. I've checked the color of my oil a few times and did not look like it needed to be changed. I've seen a good amount of people have this same exact problem, happened to a buddy of mine his just came on the other week when he hit 10,250 miles. Seems to be a software bug of sorts with the 15 models from my experience. Will be changing my oil within the next week or 2 because I'm coming up on 5,000 miles since I last changed. Will let you know if the light disappears after that.