Internal Hub Generator Coil Short-Circuit

This condition occurs when the internal copper windings within the dynamo hub suffer an insulation breakdown, typically due to age, excessive heat, or moisture ingress. When the coils short-circuit, the hub loses its ability to induce an electrical current as the wheel rotates. This is a terminal hardware failure that cannot be repaired by the user, as most hub dynamo shells are sealed and require professional service or complete unit replacement.

Sources