W164 Headlight Switch

On the Mercedes-Benz W164 M-Class / ML-Class (2006–2011) and its platform sibling the X164 GL-Class, the headlight switch is a comprehensive electronic module mounted to the dash. It doesn't just control the headlights; it communicates directly with the vehicle's Front Signal Acquisition Module (SAM) via the CAN-bus network to manage high beams, fog lights, and parking lights.