Brake pad wear sensors are electronic components integrated with the vehicle’s braking system to monitor brake pad thickness. Typically located near the brake pads themselves, these sensors utilize a physical or electrical contact that diminishes as pad material wears. When pad thickness reaches a predetermined critical level, the sensor triggers an alert—illuminating a dashboard warning light—indicating impending brake failure. Sensor designs vary, employing either a simple conductive contact or a more robust inductive system for wear detection. Replacement is typically performed concurrent with brake pad service to ensure continued accurate wear monitoring.