Isblkroof

So i have a 2002 is300 and its a manual. The snow button hasn't worked since i got it and im trying to figure it out before i have to go to the dealership..... Trac button works and all that good stuff but when i press the snow button nothing lights up and i dont feel anything so since it doesnt show up on the cluster and i dont feel it kicking in im guessing its not working. So if you have any ideas on how to fix it let me know Thanks.