Other dashboard warning lights
For cars fitted with ESC (electronic stability control) the warning light should come on and then extinguish after a few seconds. If it stays on to warn of a fault, the car will fail. This also applies to warning lights for cars fitted with electric power steering, brake fluid warning lights, tyre pressure monitors, air bags lights and seat belt pre-tensioner warnings.
http://www.motchecklist.co.uk/mot-2012-changes.html
It's worth a read for others,especially those who've modified their lights in any way.