I'm just going to assume that by green display your taking about is a dash
neutral indicating light?
If it's not just a Neutral indicator:
If the whole dash is black then you have bigger issues, like dead battery, dirty/bad battery connections, blown fuse.
If it is just a neutral indicator:
Double check that all levers are in the neutral/off position, PTO levers is #1 oops I bumped it in the on position.