Controller area network (CAN) can not deal with eventtriggered traffic and timetriggered traffic simultaneously and efficiently in real time system. Considering the flexibility of design and schedule, flexible time triggered CAN (FTTCAN) was introduced to manage the power transmission system in vehicle and build up in vehicle networks with CAN by linking with gateway. The method of allot messages in scheduling table (SchT) in synchronous phase was introduced. The analysis results of system such as real time performance and dependability verified the proposed scheme was feasible and showed perfect performance.