Front view of the Ultimate Ears Wonderboom 2 speaker.

Wonderboom 2 Charging Light

The Wonderboom 2 charging light is a single LED on its top panel, close to the front.  This lets you know battery status, whether it’s draining or charging, or whether it’s low or not when discharging.  However, it does not show charging progress. Nor does it indicate how full the battery is at a given time while charging. And it does not show much energy remains when discharging. But it does change color when the battery reaches almost-dead state. So in this post, we describe how to read the Wonderboom 2 Charging Light.

Wonderboom 2 Charging Light: How to Read the Light

1. The Lamp is OFF 

When you power down the Wonderboom 2 with no charger, this lamp goes dark.  The lamp is also OFF when the charger IS present and the battery is full.

Picture of the top of the Wonderboom 2. Showing the dark -Power- button.
Top view of the Wonderboom 2. Showing the dark -Power- button.

2. Wonderboom 2 Charging Light Shows Charging Progress But Does Not Tell How Much Progress

The status light flashes in a gradually dimming and brightening pattern white as the speaker charges.   On this speaker, this LED is the only visual indication that charging is happening.  But it does not tell how far along the charging is.

Picture of the -Power- button glowing white.
The -Power- button glowing white.

This slowly fading and brightening white pattern displays while charging, whether the speaker is OFF or ON.

Back view of the speaker, showing the charging cord connected.
Back view of the speaker, showing the charging cord connected.

3. When the Charging Light Goes Out, Then Charging is Complete

As speaker charging continues, the light keeps slowly blinking white. Furthermore, battery recharging is over when the lamp goes out, or turns solid white.  It turns OFF when the speaker is OFF, and switches to a solid white glow when the speaker is ON.

The battery recharge cycle finishes when the speaker status lamp turns OFF. Even with the AC charger running, the lamp does not glow when battery is full. Not unless the speaker itself is running.

4. Wonderboom 2 Charging Light Does Not Tell How Much Charge Remains Until It’s Really Low

When you disconnect the charger, what was the Charging Light becomes the battery charge left indicator.  Well kind of.  If it glows solid white, then the battery has some play time left. Anytime the speaker is ON, you can hear battery status.  Just press the Volume UP and Volume DOWN buttons at the same time to hear it. The number of blinks in the sound indicates battery fullness.

But when the battery goes very low, the lamp turns from solid white to solid red.

Picture of the red glowing Charging Light light on the Wonderboom 2.
The red glowing Charging Light light on the Wonderboom 2.

Note that once this light turns red, the speaker will not power up again until you charge it a little. Indeed if you try to boot the speaker with a nearly dead battery, the lamp blinks red rapidly. Then the speaker shuts down after a few seconds.  So this blinking signals that the battery needs a charge before you play the speaker again.

Other Wonderboom 2 Posts

    1. Wonderboom 2 Battery Indicator Explained
    2. Wonderboom 2 Charge Time
    3. How to Turn OFF
    4. Firmware Update Routine
    5. How to Connect to Alexa


    1. Official Wonderboom 2 Support Page
    2. Where to Buy the Wonderboom 2