Zero Turns

rz5424 zero turn mower has no spark.i have the Kawasaki motor. Mower would not start. I found that it had very little to no spark. i replaced the coils, and still no spark. I disconnected the single black wire that goes to the coils and it was able to start and ran great.
This seems to be some kind of kill switch issue. My question is how to i figure out what is causing the issue?

thanks
Dan