What indicates a short circuit between points A and B?

A resistance measurement of zero is indicative of a short circuit between points A and B because a short circuit essentially creates a path with negligible resistance. When two conductive points are directly connected, it allows current to flow freely with very little opposition, leading to a resistance measurement that approaches zero ohms. This condition means that any connected power source will deliver maximum current, which is a key characteristic of a short circuit.

In contrast, high voltage readings or overheating of components may point to other electrical issues, but they do not specifically confirm a direct short circuit between the two points. Similarly, a current drop in the circuit instead suggests that there is resistance behaving as part of normal circuit operation or potentially an open circuit, rather than confirming a short. Thus, measuring resistance and finding it to be zero provides the clearest and most direct evidence of a short circuit occurring between the specified points.