What happens when you turn the key? Do the dash lights go out? Have you looked at the battery cables? Try taking them off for a few minutes, make sure the connections are free of battery acid and connect them back to their post.Hey guys I'm new to this site, I do not own this car it is my moms and we can't seem to figure out the problem. So it is a 2006 mustang GT it starts fine and runs perfect until you shut it off. If you try and start it anywhere from 5-45 mins after the car is shut off it will not start, all lights come on like normal, no codes, no check engine light, will not even turn over. has been to a Ford dealer twice and they can't find the problem.
You could also turn the key to the only position, turn your lights on and physically move the two battery cables around...look and see if that causes your lights to go out...could have a bad connection/break in connection.