Small Engines (Lawn Mowers, etc.): John Deere 318 will not start, no spark, john deere 318 lawn tractor, john deere 318

Question
My father tried to jump start a John Deere 318 lawn tractor with a charger/starter.  He hooked up the leads backwards.  The battery has been charged and will turn the engine, however, it will not start.  There is fuel evident, however, I can verify that there is no ignition.  Has something been fried by reversing the polarity of the starter/charger?  The fuses are ok and the electronic box will pull in the relays.  Lights on the dash seem to work ok.  The coil has 9.8 ohms of resistance and continuity verified.  Could this be a fried black box or coil?  Thank you.

Answer
 Hello Brooks:

 Any of the Safety Switches could cause this problem. The Ignition Module could have been fried. Im leaning towards a Safety Switch or A Fuse that was Missed. Take the Shutdown wire off from the Coil and see if the Engine gets fire. If so then a Safety Switch is the Problem. If not then Check the Ignition Module. Hope this Helps.

 Good Luck

 Respectfully

 John