This bill, known as the Collision Avoidance Systems Act of 2025, aims to clarify federal regulations to explicitly permit the installation and use of pulsating light systems for high-mounted stop lamps on motor vehicles. It defines a pulsating light system as one that rapidly pulses up to four times for a maximum of 1.2 seconds upon brake application, then converts to a continuous light, with a minimum 5-second lockout period before subsequent pulsing. Upon enactment, Federal Motor Vehicle Safety Standard Number 108 will be considered to allow these systems. Furthermore, the Act mandates the Secretary of Transportation to promulgate new regulations within 180 days. These regulations will update Standard 108 to include specific performance-based standards for pulsating light systems and formally authorize their use on vehicles covered by the standard, enhancing rear-end collision avoidance.