2005 Saturn Ion Electric Power Steering

Hi, I got a problem with EPS, when I driving My car, after 5-10 minutes power steering light comes on, and I lose power steering, pull off on the side of the road, turn car off, restart, put in drive and the light comes back on, with the same effects.
I checked 2 fuses, and they are ok.
What can be the problem? And where to search?
I went to GM dealer, they asked for 1,000$ for repair, without any guarantee that this will help.