If you are driving on an icy road, and take a turn too tight, the vehicle may be forced to apply pressure to one of the brakes to prevent the car from loosing control. In this situation the VSC indicator light will light up to alert you that the action was taken, and remind you to possibly slow down.

So Vsc light is always a good thing which you must have...


TRACTION CONTROL:

It isnecessary for

1) Useful during diagnosis of a mechanical problem.
2) As a workaround if a dangerous system problem with the traction control is known but repairs may need to wait a few days.
3) Enabling dynamometer testing (for power or emissions) on a 2 wheel drive vehicle.
4) On front wheel drive vehicle, to prevent cyclical gyrations of the power steering during excessive hard acceleration (machine controlled by negative feedback).
5) On rear wheel drive vehicles, expert driver may wish to use high torque to break traction for a controlled slide around a turn.