Genuine OEM Volkswagen Engine Control Unit Relay, part number 165906381. This electrical relay is a crucial component that controls the power supply to the engine control unit (ECU), enabling proper engine function and management. It acts as an electrical switch, allowing a low-power signal to control a higher-power circuit. Weighing 0.037 kg, this relay is built to precise factory specifications. Choosing a genuine OEM relay ensures correct electrical characteristics, reliable switching, and long-term durability, preventing intermittent electrical issues that can affect engine performance.