Mine started acting up at 18 miles. Power steering light was yellow, and shifting was hideous. It would catch for a sec, then like it was in neutral. Rev the motor and it would catch again. Manual and sports mode were totally inoperable. Took it to the dealer, and demanded a new machine...turned out it was a loose ground wire located close to the dipstick. The dealer tightened the nut on the found lug, and it's all good now.
Could you be more specific on the ground wire? I have 92 miles on my machine. The EPS light comes on very dim, then bright, then off, then dim....... It acts exactly like a loose ground wire somewhere. The EPS seems to work but the warning light is not acceptable. I took it back to the dealer, they fixed a key switch and the light stayed off for about 10 miles but then started acting up again.