Anti Lock light on

What is your question?

My anti lock light is on and staying on. The brakes seem to work fine. I have a very steep driveway and sometimes there is a slight burnt rubber smell after coming down the driveway (I have my foot on the brake while doing so) After some research it looks like it's probably an abs sensor is dirty or damaged. But would this cause the burning smell when coming down a steep hill? I just want to make sure all this is related so I don't fix one expensive part and then have another expensive problem. Thanks!