In the domain of vehicular communication, the announcement protocol serves as a critical mechanism for disseminating safety-related messages to enhance traffic safety and efficiency. However, ensuring both message reliability and preserving vehicle privacy poses a significant challenge. Our proposed protocol addresses this conflict by employing synchronization of the Chen chaotic dynamical system. This novel approach achieves the seemingly contradictory goals of reliability, privacy, and accountability. Utilizing the Chen chaotic dynamical system in the announcement protocol enables vehicles to broadcast messages without compromising their identity, thus ensuring privacy. Additionally, in cases of misbehavior, the accountable vehicle can be identified and isolated from the network, thereby upholding public safety and meeting accountability requirements. Our research contributes a comprehensive analysis and simulation results, demonstrating the improved performance efficiency and feasibility of the proposed announcement protocol for vehicular communication. Leveraging the Chen chaotic dynamical system offers a promising solution to the challenges posed by message reliability, privacy preservation, and accountability in vehicular communication.