I have recently noticed that when I depress the rear defrost button on the dash, the light under the button is very dim and not as bright as the rest of the buttons when activated. This is also occurring with the front defrost and max air button back lighting. Has anyone else noticed any issues with this? The front defrost does operate when the button is pushed and so does the max air, but the back lights aren't lit. It has not been cold enough to check to see if the rear defrost is working.