Help!! Motor Runs When I Charge My Bit!
 

What could my problem be? I had been running and charging my bit all day with no problems at all. But just a few minutes ago, just after I installed a rare earth magnet, I plugged my bit into its charger and the motor began to run at extremely high RPM. I immidiately unplugged it and the motor stopped running. I have a dual battery set up and a stand alone 8 AA charger (9.6 Volt). I tried running the motor and turning with the controller and everything worked fine. however, once I try to charge it, the motor begins to run at very high RPM. I also noticed that the circuit board was very hot after I tried to charge it. WHAT COULD MY PROBLEM BE?

The ground wire on the pcb is touching the heat sink or somewhere in that general area. had the same problem.

Just look at the black wire on the bottom of pcb and you'll see what you need to do.