Abstract: The trackside safety platform is a universal safety-critical computer system certified by SIL4 European standards. Signal products such as zone controllers, line controllers, and radio block center developed based on this platform have been successfully applied in multiple rail transit projects. In order to facilitate the configuration management, operation monitoring, and fault analysis of on-site signal products, a maintenance tool software - the maintenance detection subsystem - has been developed for this platform. This tool software can be used to complete configuration data settings and software version checks before product delivery. It can provide operation monitoring and real-time alarm functions to facilitate on-site maintenance personnel to grasp the operation status of the equipment. Equipped with comprehensive log recording and convenient log export function, it greatly improves the efficiency of on-site signal system operation data collection, facilitates product development personnel to trace the process of on-site problems and accurately determine faults. The maintenance tool software adopts the MVC design pattern, which separates the receiving, parsing, and interface display logic of data collection messages, making its code easy to maintain with strong scalability. Its user interfaces can be flexibly customized according to the personalized needs of signal products and its support for new protocols can also be rendered. This maintenance tool plays a crucial role in ensuring the stable operation of the on-site signal system, and can also serve as a tool for testing and debugging signal products in the laboratory.