4 Wheel drive switch


I own a 2006 Ford F-150. I have a problem with the 4 wheel drive switch. It wont work! A light will go on when it is turned on and you can feel it when it engages. Nether of these two happen. I looked at the fuse box, but it is unclear to me which one it is. Even when looking at the owners manual. Do you think it is a bigger problem then electrical? what should I do?

Also so can you estimate the coast of repair? Wether it be electrical or something more series.