The service centers are just parts swappers. Always have been. Most diagnosis is done by engineering at headquarters. Don't get me wrong, every SC has access to the cars logs, but they are so in depth, one has to know what they are looking for to get any real meaning out of them. Unless it's what you do every day, reading logs is not easy.Wow. How on Earth is that a good engineering decision? "Yeah, let's make it more difficult for the folks who troubleshoot and repair these cars to figure out what went wrong. Good idea, right?"