Slam testing is an important test for evaluating the fatigue resistance of a door plate module prior to its delivery to the car manufacturer. In such testing, one experimental specimen is subjected to more than 8 days of continuous testing. In this paper, a vibration testing method is proposed that is intended to replace the conventional swing-type slam testing of a door plate module. The method is based on the concept of duplicating the same failure mode at the clamping part of the glass in a door, where the stress is concentrated. After a review of the feasibility test performed with a multi-axial vibration simulator, a similarity test for a door module was developed that uses a uni-axial vibration exciter that required the door glass to be exposed to a critical spectrum of vibration for less than 2 h. The validity of the proposed testing method was demonstrated by comparing the failure modes of both the conventional and the proposed slam tests.