The wayward turret and airsoft gun are examples of a fried board. I am not sure what component has failed, and because the replacement boards are so cheap, I am not sure you could fix it at a lower cost anyway. Good thing there is a ready supply of these cheap ESC boards. If it wasn't for that these Heng Longs would never have grown in popularity as they have. Guys like to call these toys but to me what differentiates these from a toy is the ample supply of parts available.