A lot would depend on if your points were open or closed wouldn't it? If the coil is hot with the switch off then it should not make a differences. With the switch on it compleats the circuit between the coil, points and ground every time the points closed. If the points were closed then you would be drawing current and draining the battery, along with over heating the coil and burning the points. Part of your question makes me think at this point you are guessing that the battery might be drained.