If yours like my DF150, 1.  remove the red kill switch key  2.  turn on ignition 3.  lift kill switch button 3-5 times.  4 Replace key
"No Oil" should come on every 100hrs, recommended service interval for these engines.  I think it is the Japanese thinking they are being funny using "No Oil" vs. "Service".  



 Scared the sh*t out of me first time I saw that message.  Happened to be off Cutty at the time.