[1] Before the start of service, a maintenance vehicle leaked oil onto the tracks from Buona Vista MRT station to Clementi MRT station until the junction with Ulu Pandan Depot.

As a result, the train had to stop for a longer time at the station to recharge its batteries.

At 7:50 a.m. on 5 August 1993, the 12th train, collided with the stationary C151 at Clementi while it was recharging its batteries, resulting in 156 injuries.

[3] In the aftermath of the crash, SMRT said that it would replace the faulty maintenance locomotives and purchase new ones.

It also introduced a new policy for station managers to inspect tracks for oil or foreign objects before the start of service.