Hi. My mower won't start. When. I turn the key one click to run, the power comes on, the screen comes on, and I hear the ticking of the warmer. When I turn the key to start, I hear either one click or no click and everything turns off and the screen goes blank. I have to disconnect the battery to get it to turn on again. The battery is good. I took it to the dealer and they load tested it. I am sitting in the seat, the brake is on, the handles are out and the PTO is disengaged. Even if the safeties were engaged, it would not turn off like this, it just wouldn't start. Any thoughts? Thanks!