The use of advanced electronic control unit (ECU) in automotive industry is growing. Information collection and processing in systems with many ECUs face interruptions. Various bus standards for vehicles, such as Controller Area Network (CAN), are introduced in order to improve the overall performance. Optimization of CAN-bus is a challenging issue because of the recent needs including electric propulsion or driver assistance that involves more stringent real-time constraints. In this paper, we present a method to optimize CAN-bus for vehicle automation through microcontroller based design. The 'control system' and 'comfort system' of a vehicle are modeled using CAN-bus. The proposed CAN-bus system is evaluated by analyzing the frame response time using RTaW-Sim (a CAN simulation tool). Experimental results from VisualSim simulation show that the proposed CAN system helps decrease the frame response time by more than 43% when compared with a traditional wired system used in vehicles.