 On 3 September 2004 , Hyundai Rotem , Mitsui , RM Transit Technology and dU LexBuild received an order to refurbish all 396 carriages , costing S $ 142 @.@ 7 million in total . The works included the refurbishment of interior fixtures , the addition of wheelchair spaces , the upgrading of onboard communications equipment , enhancement of the public announcement system , and general improvement of the cars ' appearance . SMRT Corporation said the reasons for refurbishment were wear and damage of important components over the past two decades and water leaks from the air @-@ conditioning system on some trains . The company chose this option instead of buying new rolling stock , which would have cost S $ 792 million . The first refurbished train began revenue service on 5 November 2006 , and all remaining trainsets had been refurbished by the end of 2008 . 
