s or w mode
your owners manual will tell you all of this. I think the D+ is not for normal driving but for when you need that little bit of extra power.
"S" stand for Sport for quick start or for summer driving "W" stand for Winter for preventing the rear wheels spinning in wet or snow road condition or for winter driving.
S is "Standard" and W is "Winter/Wet" for snow/ice.
Looking for a Used C-Class in your area?
CarGurus has 31,585 nationwide C-Class listings starting at $2,500.
Search Mercedes-Benz C-Class Questions
Mercedes-Benz C-Class Experts