No ignition spark on john Deere m665

I have a john Deere m665 that is not getting fire to plugs. I have changed plugs, cleaned coil contacts on flywheel, and checked continuity on seat switch. Still haven't found anything. Seems to me that parking brake switch or the control leaver safety switches wouldn't cause this because it keeps it from turning over. It turns over fine. (Checked them any way. Only one I haven't checked is pto switch. I made sure it was disengaged, but have not checked switch. Any help is much appreciated! Will Travis