IIWPG protocol for the dynamic testing of motor vehicle seats is a test procedure for ratings of seats and head restraints for neck injury prevention in low speed rear impacts. In this study, we evaluates the performance of the car seat in the dynamic test was enacted by IIWPG and initial geometry test that has been enacted by RCAR to vehicle being sold in the market today. 6 models became the A and G in the final rating that reflects the results of the dynamic test and Initial geometry test. Electronic active head restraint was found to be allowed to operate quickly headrest, it is very effective in the prevention of neck injury in support of the head of the passenger. we suspects that this is contributed lower the value injuries reduce the relative acceleration between the chest and head. It is determined that the expanded application is required up to the small car because rating appears high in the vehicle equipped with the electric active head restraint. In addition to the evaluation of the impact velocity and collision direction, neck injury continued research to present proposals for improvement is required future.