[6] Upon entering service in April 1993, the new trains gradually replaced the previous 1962 tube stock, which was completely withdrawn two years later.

[4] These would be the only tube trains to use this type of DC motor, and would be the last newly built train on the London Underground with DC motors, and the second to last in the United Kingdom, only succeeded by the Phase 3 MTR Metro Cammell EMUs in Hong Kong which continued to be produced until the transfer of sovereignty in 1997.

[citation needed] After the initial construction run, an additional ten two-car units were built for British Rail for the Waterloo & City line, which at the time was part of the national railway network.

Transport for London and Metronet closed the Waterloo & City line for five months from April to September 2006 to allow major upgrade work on the tunnels and rolling stock.

The refurbishment of the trains saw them painted in the London Underground white, red and blue livery in place of the Network SouthEast colours used since the stock's introduction.

The ATO is responsible for operating the train whilst the ATP detects electronic codes in the track and feeds them to the cab, displaying the target speed limits.

The driver is only required to open and close the doors and press a pair of "Start" buttons when the train is ready to depart.

[citation needed] The entire 1992 Stock fleet was withdrawn from service the same afternoon, and the Central and Waterloo & City lines were closed for several weeks until modifications were made.

This included fitting new traction-motor bolts and secondary brackets to prevent a loose motor from striking the track and causing further damage.

[citation needed] Some of the noticeable changes included the addition of the new "Barman" seat moquette, new brighter interior lighting and the installation of new window frames.

This included repairing water ingress and replacing a large number of parts with a much simpler design, saving costs on future work and cleaning up the appearance of the front end.

This includes a complete overhaul of the interior and adding new features such as new wheelchair spaces, PIS (Passenger Information Screens), and CCTV installed throughout the train.

[citation needed] In 2006, the Waterloo & City line was closed for several months to allow for track and signalling upgrade works.

During this period, the 1992 Stock units in use on the line were removed by crane from Waterloo depot and taken by road to Wabtec Rail in Doncaster for refurbishment.