|As far as I know, the laptop does not identify S-video cable. You should direct S-video signal to TV by pressing the Fn key continuously and then pressing the video out key several times until you see a picture on TV.|
But first you may also have to enable / activate S-video reception in the video settings menu of the TV set.
A SCART connector has composite video / S-video / RGB / YUV signal capabilities. It depends on your TV set's capabilities to accept one or several of those signal types through a SCART connector.
Normally a TV set should be able to identify the signal and automatically adjust its properties to accept the type of signal input to it. But some TV sets require you do it manually.