2005 cady sts dies while driving on 2005 Cadillac STS

My 2005 caddy sts just dies at any time. it could be while idle, highway driving, or in town driving. everything shuts down. no dash lights, no radio, no turn signals, no anything. after about 10 seconds the dash lights up, and says put car in park to start, which I do, and it starts fine. Does anyone have any idea what may cause this? Also, had it checked, and it is throwing no codes.

Asked by for the 2005 Cadillac STS