Power controller for a vehicle

A power controller for a vehicle can operate electrical load upon stopping of engine or turning OFF of a key switch, and lowering of remaining capacity of a main battery (1) can be prevented. The control system has a control portion controlling operation of a power generator (3) and an electrical load mounted on an automotive vehicle. The control system also includes remaining capacity measuring means (21) for measuring a remaining capacity of a battery. The control portion drives a predetermined power load when an engine is stopped or a key switch is held OFF, and operation of the power load is stopped when a remaining capacity of the battery measured by the remaining capacity measuring means (21) becomes smaller than a predetermined value.