GS 400 all of a sudden died out.
 

I have a 2000 Gs400. Started up fine, drove it around 25 miles and pulled over to put gas. It was bellow the red line. I went ahead and started it again no problem. As I was driving two miles all of a sudden all the lights came on and power was out. Luckily it happened just before getting on the freeway. Tried turning it on and it cranked over but no start. Tried a few more times and it seem like it wanted to start but nothing. Had it towed to a shop as soon as it got dropped off and went to show the mechanic dam car turned on like nothing.
Mechanic put on a scanner and no codes pop up. He’s had it for a week been driving like nothing ever happened. Im going to pick it up, but now I’m worried that one day it’ll stop in the middle of the freeway and end up getting rear ended. Has anyone ever had this issue.
Thanks.