If you feel cold or hot in the car,turn on the heater or air-conditioner. You can also switch on the sound system to listen to music or the radio while driving. There are some other ways to make your drive smoother and easier,such as power seats,GPS and a car security system. All these electrical facilities are distributed throughout the car. What makes all the circuits in the car work together? This would be the car’s circuitry and power distribution equipment.