I have found it very, very difficult to get the smoke back into the speed controllers once it has been released!!
This is very disappointing to have happen, especially when you are new to the game.
Go to the LHS and get them to look at it, but be prepared to buy a new one as repair will be expensive.
NOVAK has some excellent budget priced ones.
No matter how good you are in this game, you want the reverse polarity protection!! Every one has a brain fade now and then.
I must say that it is certainly a whole lot more entertaining when they start to burn while you are out racing, especially when everyone can smell it and you get a smoke trail from your car. Very Cool!!