I don't often use the radar cruise control, but when I have, it's worked perfectly, even bringing the car to a complete stop. But today I had the strangest thing. It was on, approaching a stop light. Car started slowing down along with the car in front. When it hit 20mph, the cruise control disengaged and flashed the warning that it was off below 20mph. Did it do this because it was cold? Sensors were all working because it maintained distance properly right until it turned itself off. Good thing I had my foot on the brake or would have rear ended someone.