The development of Electronic Control Units (ECUs) is one of the aspects that increases the efficiency and functioning of modern hybrid vehicles. The design and integration of microcontroller-based ECUs were added to the features of the Controller Area Network (CAN) protocol. Using CAN bus communications, it intends to build a strong and efficient platform for quick data transfer between different vehicle subsystems. The approach further refines the control of the operation, optimizing parameters like energy management and vehicle speed. Configuration of the microcontroller units (MCUs) to monitor and control critical functions of the hybrid vehicle such as powertrain, battery management, and regenerative braking, as well as communication through the CAN bus, has assured reliable and high-speed transmission of important data such as State of Charge (SOC), speed, and other key parameters. The system architecture integrates these MCUs with sensors and actuators, forming an interlinked network that is capable of dynamic decision-making to improve energy efficiency. This paper provides an example of how simple microcontroller-based ECUs can be employed in hybrid vehicles to streamline communication and control. The CAN bus integration enables scalable and flexible vehicle architectures for future advancement in hybrid and electric vehicle technologies. The development also provides inputs toward intelligent vehicle systems supporting future automobile trends for energy-efficient and sustainable transport solutions.