Riding Mower Won't Start?

I have a John Deere L100 riding mower. The battery is good. I had the solenoid checked by a John Deere service center. It checked good. I replaced 3 safety switches. I put a screwdriver on the big posts of the solenoid, starter motor will activate. I turned the key and lights will come on, but nothing else. The fuse is also good. I checked the ignition switch on meter, it checked good. What else do I need to check?