This ECU is compatible with idling shutoff features. The ECU detects the throttle operation of the rider, the temperature, the air pressure, and other environmental conditions and then issues commands regarding airflow as well as fuel injection, spark timing etc., to various devices, so that the engine operates at it’s optimum state. This ECU incorporates the AC generator (ACG) control with conventional ECU functions in a single unit to directly turn over the engine, resulting in a quiet startup and a smooth engine restart after idling shutoff. By conducting precise heat simulation testing to optimize component placement, we have developed this unit, resulting in a heat dissipation structure capable of withstanding a steady flow of ACG current.