I don't visit very often so my belated answer may not be of any help. Your 960 is the same model year as mine so I'll try to contribute what little I know. The W mode selector operates differently than the E and S. When pressed, the W button does not stay down and it selects and deselects the Winter mode alternately with each press. The steady orange up arrow light on the dash indicates the mode's selection. The Economy and Sports mode selector buttons on the other hand stay down when pressed. These modes can not be deselected per se and must be replaced by the other of the two modes by pressing down the other selector button. Hope this clarifies the workings of these buttons.

I have the green book on the electrical system for this year model but I am not at home right now. I can later take a snapshot of the relevant page for you regarding the wiring if you still need it.