Signal Maintainer Practice Test

In CBTC systems, AVS stands for Auxiliary Reverse Stop Drive. This describes a supplementary control path that can command the train to reverse and then stop, serving as an auxiliary function separate from the main drive control. The idea is to have an extra safety or recovery capability for specific operational needs, such as repositioning the train or handling abnormal situations, without relying on the primary propulsion path. The other options don’t fit CBTC terminology: they describe more generic concepts like surveillance or general vehicle systems, rather than a specific auxiliary reverse-and-stop function.