To wrap a bow around this issue. It turned out that I had a loose connection from battery to main fuse panel.

After replacing the DSC module I was still having the same symptoms. Thanks to Matt and Dave, this time I read the codes before turning the car off. This time I saw a low voltage error. I had thinned out my wiring a couple of years ago and apparently the main connection had worked its way loose. I went back and looked at all of my data and I could now see where the car was actually turning itself off, usually under hard braking.

Thanks everyone for their help.

 

Glad you got this solved!