My vehicle display has been showing a message that the key fob battery is low. I did replace the key fob battery. It did start, drove it around. About 3 hours later car doesn't start. And dashboard display showing this. The voltage went down to 9.4 anyone had this issue

Possibly battery...

 

Two immediate checks come to mind

1) Obviously check the battery
2) Alternator

If its not one of those 2 items, then I'd suggest getting a professional at that point.