Ever increasing requirements regarding automotive safety have led to major innovations in the field of crash safety. With a greater emphasis placed on weight reduction, the ground vehicle industry has increased the use of higher strength, thinner gauge steels, particularly by using various new grades of high and ultra-high strength steels. Choice of a particular High strength steel HSS will depend upon such factors as cost, formability, fatigue resistance and weldability, in particular spot weldability. A modern car structure may consist of several thousand weld-type connections, and failure in these connections plays an important role for the crashworthiness of the vehicle. Therefore, accurate modelling of these connections is important for the automotive industry. This paper presents the latest investigation of the strength of steel grade spot-weld joints. This study shows a developed simplified spot-weld model in crash simulations to reach the best collision characteristics of the car to meet the Federal motor vehicle safety standards (FMVSS) requirements.