The Jabra BT5020 Bluetooth headset is equipped with an LED light which is designed to indicate the status of the headset to the user. The headset will flash different colors when it is trying to indicate various functions such as low battery or an incoming call.
According to Jabra.com, when the LED light on the Jabra BT5020 is flashing every second, it is indicating that you are in an active phone call.
When you have an incoming phone call, the LED light on your Jabra BT5020 will alternate blue and green flashes.
When your Jabra BT5020 is about to enter standby mode, the LED light status indicator will flash blue every three seconds, for one minute, and then turn off.
The LED light on your Jabra BT5020 will also flash red, green and yellow depending on the amount of battery life left in the headset.