Materials usually get damaged or break under the thermal stress from repeated heating-and-cooling cycle while bolted to another material with different coefficient of thermal expansion (CTE). This study uses finite element analysis (FEM) to simulate stress distribution and deformation of car TV bonding material. The car TV bonding material bolts together plastic and Electro-Galvanized Steel Coil (SECC), and is applied stress under bolt preload and temperature change. In this case, we have the General Specification Electrical Function for reference, and discuss the improved plan of adding elastomer between plastic and SECC. The preliminary result shows that elastomer can significantly lower the stress from thermal shock. The effective stress of material with elastomer’s joint is 50 MPa, which is superior to 35 MPa detected from the material without elastomer’s joint.