I have a CM1000 (series 4) that started with my son, but when my wife tried to true in on, it smoked and won't turn on. Even days for it to cool down, it doesn't turn on. The charging circuitry works; batteries charged; the motor spins if I shorted across the red wires to the switch; 27V appears across the terminals to the battery+ and motor+; also 27V across the switch solder joints on the board; 0V across breaker. My diagnosis is the switch is bad. I know several places to buy a switch, but before doing so, I'm checking to see if anyone has any experience with this issue.