originally more than one unit could be coupled and be controlled remotely by the first locomotive using a system called "comando multiplo"; on the central part of the cab there also was a door that enabled the crew to pass from one locomotive to another in case of problems. however, because of safety issues and the imperfect reliability of this system (there were no instruments indicating the status of the slave locomotive, so it was not certain if it correctly made a transition or not, for example), it was abandoned and then disassembled.