I have a 2002 660 and was riding it the other day and had to use 4wd. When i pushed the button to get out of 4wd the differential light came on and when i pushed the 4wd and then the diff button the light would not go off. Today i turned the switch on but not start the light s still on. I can push the buttons and hear a click. What can i do and can i still use it? thanks