This paper presents the results of a systematic analysis of 91 relevant studies to gain a deeper understanding of the role of generative AI in autonomous driving system (ADS) testing. Focusing primarily on scenario-based testing, we present six major application categories of ADS testing using generative AI. We analyze various datasets, simulators, ADSs, metrics, and benchmarks, along with a review of their effectiveness, and identify 27 Limitations. This provides an overview and practical insights into ADS testing using generative AI, highlights existing challenges, and suggests future research directions in this rapidly evolving field.