Mower having electrical problems. When I try to start, it clicks or does nothing. I have replaced the battery and the electric relay with no help. I can jump it by connecting a jumper cable from the battery to the starter with the key on and brake down. It is also won't engage the blades. When I lift the PTO, the hour meter goes off but the blades don't turn on. When I turn off the PTO, the hour meter is back on. I have replaced the PTO switch and the seat safety switch but no luck. Any ideas?