brushed ESC blown
 

My son has an ECX Torment SCT and he told me he went to the plug the battery in (deans connectors) saw some sparks...Now when I plug the battery in the motor goes runs at full speed and the steering servo doesn't work. The motor will also run with the esc switch turned off. Is it possible the ESC blew?

edit: I also tried throwing in a spare motor and the same thing still happened.

Yeah, you probably melted some FETs.

That's what I'm thinking too. I think he didn't have the plugs in the right position and tried jamming it in (which why it would've sparked). Maybe I should try switching him over to EC3 connectors or something.

Use a multimeter in continuity mode and check for shorts between the battery negative and motor negative. You may find a short there.

Most Brushed ESC use N Channel FETS which means the motor gets constant battery positive and the negative of the battery is switched to the motor negative side. Shorted FETS would result in constant running.

My son has done this same thing. Must be a way for parts makers to sell more parts. I think the cheaper esc's just pop instantly when they get reverse polarity.

The expensive ESC pop quite quickly as well, you would be very lucky indeed if you got away with it.

With large capacity batteries (amperage) the poor FETS don't stand a change when they get reverse polarity.