I posted my experience with my SSN back in August where it took 40 days to get my car back. Mine was the battery itself. When mine died, I decided to leave the car on so the dealer can troubleshoot with the car in complain mode. I was hoping they would be able to pull codes. However, when Ford Roadside assistance told me the wait would be an hour, I decided to try and restart the car...turn off, open door, close door, turn on...but it still got SSN. Then I called AAA and got the car at the dealer in 30min.
Unfortunately, there were no codes available, but they were able to hook it up and run tests that produced error codes. They worked with Ford to diagnose. They packaged up the battery for Ford to fix and they sent it back.
I don't want to jinx anything, but no complaints so far....knock on wood. However, I do keep all the documentation on this just in case.