D1 multiple unitD1 is a 4-car diesel multiple unit train built in 1960s-1980s by Hungarian producer Ganz-MAVAG for Soviet railways.D1MIn 2012, Moldovan Railway and Electroputere VFU company in Romania started a complete modernization program for D1 units, with most of the parts changed, including installation of a new engine by Volvo Penta. In addition, the refurbished units were equipped with air conditioning system, wireless internet access points, and disability access ramps.