Reply to "PS-2 locomotive only goes forward when horn button is held down?"

Since controller seems ok it appears the engine thinks it is in DC conventional mode.  So a net positive voltage (horn) is FWD and a net negative voltage (bell) is REV. Since the controller appears to be ok driving other PS2 engines, there is a simple track voltage measuring circuit that might be giving faulty data to the processor chip that calculates voltage level and voltage type. I think it needs to be looked at by a tech.