The Micro-hybrid technology otherwise called as stop start system offers a significant improvement in fuel economy particularly in urban driving conditions, where more often the engine idles unnecessarily at traffic signals/jams. Micro-hybrid technology stops the engine at traffic signals/jams and starts the engine automatically on clearance of traffic signals/jams leading to reduced fuel consumption and emissions. This is achieved by monitoring several vehicle and engine parameters through appropriate sensing elements.In this study, the system architecture and functional definitions of start/stop system is defined. Equivalence class, boundary value and decision-table testing are used to generate test cases. On generation of test cases, their relevance on on-road robustness and scope for optimization towards time/efforts are analyzed. In the process, a matrix of different conditions and criteria are formulated. Under these conditions, the system behavior is evaluated. It involves testing of stop release conditions, stop request conditions, start release conditions and start request conditions. The actual result of the testing is equated against the expected results.In this paper the system architecture, functionalities and definitions are briefly covered. The methods used for test case generation and their application for start/stop functionality are explained in detail and their correlation for on-road robustness is summarized.