Having a working brake system is essential if you want to avoid rear-ending the guy in front of you who stopped suddenly. Unfortunately, your brakes need to do more than just bring you to a halt; they also need to warn other drivers when you're stopping so that they don't plow into your trunk. That's why it's critical to replace a faulty brake light fail switch as soon as possible. Besides, the highway patrol can issue you a ticket if your brake light fail switch isn't working, and that'll cost you a pretty penny.