The dynamic characteristics of automotive structures are largely influenced by joints. The complex structures such as car a body-in-white is made from thin metal sheets and joined together by several types of joints such as spot welds and bolted joints. The integrity and dynamic characteristic of the structure are highly dependent on these joints. The defective and inaccurate tightening of the bolts during the assembly process could degrade the integrity of the structure and alter the dynamic characteristic of the vehicles. Early detection of the presence of damage in the structure is very important so that necessary actions can be taken to prevent further problems to the structure. In this paper, the damage detection via vibration based damage detection is used to identify the presence of damage in a bolted joints structure. In order to check the validity of the proposed method, natural frequencies and mode shapes of the initial finite element model of the undamaged structure and the finite element model of the damaged structure are compared with the experimental counterparts. The model updating method is used to improve the initial finite element model of the undamaged structure and the damaged structure as close as possible to the measured data.