Yes, on many pieces of equipment the PTO switch is part of the starting circuit. They could be related, but we don't know, because we are not there. At this point you need to go through an electrical troubleshooting procedure to diagnosis your problem. Give us results in very clear and concise terms and we will help you move forward. As I said earlier, you cannot assume or skip any steps when doing electrical troubleshooting. Something as simple as a dirty connector could cause a major problem for the troubleshooter.