Hey everyone!
I received this little 4-wheeler as a present recently. Unfortunately the ESC out-of-the-box was defective in some way. Its heat sink start burning after 20 sec of mild use and reverse just not worked properly. I had it immediately replaced with a new one and drove it around (in dirt...) for only 2 batteries time. It worked just fine.

Today I connected the battery (stock one) to the ESC while switch was in the OFF-position of course. To my surprise the ESC started "smoking" almost 5 seconds after I hooked up the battery and the cables, connector and ESC heat sink extremely burning.

I know few from electronics but this smells like a short circuit. Could this have happened due to the accumulated dirt (dust was not THAT much anyway...)? Could this be a problef of the battery?

Any ideas folks?

Thank you in advance
George