A running fault

Hi all Its my first post and sad to say its a fault one .
I have a 2008 WR250R on the last few rides out she has suddenly died while out riding the the management light comes on but goes out when the magic button is hit and she restarts with no problem. I did a check on the codes and the only one that comes up is 70 which I think is idle for 20mins error .
I love this little bike but would like to sort this problem out just in case .