Haiz... u mentioned it.... u got it.
Mechanical fault on SBS7378R on 198 today
(06/03/2009) at 7:24am.
Location: Bus-stop opp ITE Dover along AYE
The B9TL was bearing the advertisment on "READ! Singapore
(Nurturing a Nation of Readers)".
I believed the driver couldn't close the exit door. The
bus captain flashed hazard lights and tried to close
the door but couldn't. As a result, he pulled to a corner to let
the passengers alight to wait for the next bus. There weren't much
people affected except for some school children. Luckily, I wasn't
in that bus.
But wtf man... I posted my comment on 198's B9TL yesterday
and today witnessed this... so coincidental. 
It's just coincidental, and it's just a door fault, not engine
problem, so I believe bus can be back on the road within a
day.
Cheers.