 The cars were replaced with 3rd generation Class 311000 trains and taken out of service in 2006 when they finally reached their 25-year lifespans, and were stored at the Byeongjeom Car Depot until 2011, when they were finally taken off property to be scrapped or repurposed.The second batch of 1st generation trains consisted of 126 cars that were originally linked as 21 six-car trains.The cars were manufactured from 1976 to 1979 under Daewoo Heavy Industries.