The battery in your TomTom GO charges when you connect it to the car charger, to your computer or to a USB Home Charger.
You are warned when the battery level is low or critical. You lose your connection to some TomTom services when the battery level is low or critical. When the battery is empty, your GO goes into sleep mode.
Note: Use ONLY the USB cable supplied with your GO. Other USB cables may not work.