I purchased one of these neat little pistols used.  It had the laserlyte grips.  My FFL removed the cylinder to show me it was unloaded.  The laser worked then.  It worked when I got home.  When I reinstalled the cylinder it didn't work.  Is there something I need to do other than tap the button at the bottom of the grip?  Could I have accidentally turned them manually off while I was working to get the cylinder back in?  Any help would be greatly appreciated.