Low traction light

This is a very generalized answer - it might be normal considering the conditions, and I've seen it on several cars. One tire slipped slightly and triggered the sensor. If it happens in dry conditions then it could be the sensor. What's happening here is all about the tires. "All season" tires are adequate in the winter. It varies by brand, but some grip better than others in the cold. That there was ice means it was really cold. Even tires marked "winter" are going to lose traction where ice is concerned. Winter tires have a more aggressive tread and the tire "rubber" isn't as affected by low temperatures. The trade-off is they're a bit noisier and may not last as long. All season can get a bit "hard" when it's cold, have a less aggressive tread. That combination doesn't make for great traction. They are quieter, and may last longer. Depending on where you live and the driving you need to do, you may want to explore different tires. I know that's an expensive option, but it's less costly than getting hurt and losing the car. Most garages, or auto parts stores, can read the OBD2 in your car, usually free. If there's something wrong with the sensor, they'll tell you.

the light comes on when the trac. system is working. the system keeps the wheels from spinning. if you turn the switch off, light will stay on, and wheels will spin. ( short definition of system operation )