The East-West Line has started running on the new Communications-Based Train Control signalling system, the second line to do so after the North-South Line.
More than 100 train drivers took part in a five-hour trial of an upgraded signalling system on both the North-South and East-West lines yesterday.
Commuters were hit by another round of train delays early Friday morning following a two-hour delay during the evening peak hour the day before.
A power fault caused SMRT train services on the North-South and East-West lines to be affected late Wednesday night.
Commuters should be prepared for more MRT delays as testing of a new signalling system for the North-South Line enters its fourth month.
There were two delays on the North-South Line on the first two days of June, following the start of SMRT's weekday signalling tests.
The goal is to eventually have train operations capable of running at intervals of as short as 100 seconds between each train.
The East-West Line is being equipped with the same signalling system as the North-South Line but it has yet to be fully installed for trials to be conducted.
All-day trials of the new signalling system on the North-South Line, as well as the operation of the first of 57 new trains, will begin on Sunday (16th April).
The complete switchover to the new signalling system was slated to take place at the end of last year but was delayed as authorities wanted to do more tests.
A new signalling system will be tested on the North-South Line on Tuesday night (28th March), all trains will stop for about 10 minutes at around 11:00pm.
Commuters affected by a spate of delays resulting from faulty track circuits may have to wait at least a year before the glitches are resolved.
Rail operator, SMRT, said a signalling fault caused train delays along the North-South Line yesterday resulting in extra 30 minutes of travel time.
Mobile services on the Circle Line have been temporarily switched off until further notice on Friday morning said M1.
Travel on the Circle Line will continue to be disrupted, even as the Land Transport Authority and rail operator SMRT are working to solve the problem.
SMRT said in a statement that intermittent signal issues were the cause of the delays on the Circle Line and more delays are expected throughout the day.
Signalling faults caused significant disruption to North-East Line (NEL) services during morning peak hours, the fourth major incident on the NEL this year.
The North-East Line service has resumed after a delay due to a signalling fault at Sengkang station on Tuesday (Sept 8th) morning.
Train signalling issues may continue to cause service delays as upgrades to the system will only be completed in 2016 at the earliest.
A train captain who bypassed a signal point without authorisation caused a track fault, resulting in disrupted service between Tanah Merah and Pasir Ris.