The front left view of the Sony SRS XB21 speaker.

Sony SRS XB21 Battery Indicator

The Sony SRS XB21 Bluetooth portable speaker has a simple battery level indicator LED in the rear button / port panel, just to the right of the USB input port, as shown in the pictures that follow.  This displays battery status. E.g. Whether it’s draining or charging, or whether it’s critically low or not when discharging.  But it neither reads out charging progress, nor exactly how full the battery is at a given time while charging or draining. But it does pulse orange when the battery hits close-to-dead. So in this post, we explain how to read this battery indicator lamp on the XB21.

To get a more precise readout of battery percentage, see below.

How to Read the Sony SRS XB21 Battery  Indicator: Detailed Steps

1. The Lamp is OFF 

The battery lamp is dark in the following situations:

    1. When you power down the XB21 with no charger connected.
    2. When the charger IS connected but the battery finished charging to full, as shown next.
    3. And finally, this light is OFF when the speaker itself is powered ON, but the battery is fuller than critically low. This light is dark as long as the battery does not yet need charging in this case.
The dark -CHARGE- light on the Sony SRS XB21 speaker.
Sony SRS XB21 dark -CHARGE- lamp.

2. The Sony SRS XB21 Battery Indicator Flashes Orange

With the charger unplugged, the XB21 powered ON, and the battery having very little energy left, this light starts flashing orange.  The meaning here is that the speaker will shorty power off due to a dead battery and that you should put it on the charge soon to avoid play disruption.

3. This Lamp Also Functions as a Charging Light

This LED also lights steady orange (no blinking) as the XB21 recharges, as we see in the next picture.   On this speaker, the light glowing is the only visual way of telling that charging is occurring.  But it does not show how far along the recharging is, until it actually goes dark.

Picture of the -CHARGE- light glowing.
The -CHARGE- lamp glowing.

Also note that this light should never blink on and off during recharging.  If it does, then either your charger is not supplying enough (or any) power, your USB cable is defective, or you have some issue inside the speaker.

4. When the Light Goes Dark While Charging, Then Charging is Done

As speaker charging continues, the light keeps glowing,  But eventually, battery recharging finishes, and the lamp goes out to show this.  It is OFF in this case whether the speaker itself it ON or OFF. Note that the light will go dark too, if you disconnect the charger before the charge cycle has finished.

5. The Sony SRS XB21 Battery Indicator Is Not a Charge Remaining Meter

When unplugged from the charger, this light becomes the battery charge left indicator.  Well sort of.  I.e. If it is dark when the speaker is ON, then the battery has some amount of play time left, although you cannot tell how much. If it flashes, then you can infer that the battery is nearly dead.

Reading Battery Percentage

However, on this speaker, you can get a more precise reading on the percentage of battery charge left.

Picture of the -BATT- button.
The -BATT- button.

Just press and hold the Phone-BATT button until the speaker says the remaining power percent value in a female voice.

Related Posts to Sony SRS XB21 Battery Indicator

    1. Sony SRS XB20 Battery Indicator and How to Read It
    2. The SRS XB01 Sony Speaker Battery Indicator Light Explained
    3. Sony SRS X11 Battery Indicator Explained
    4. How to Read the Sony SRS XB13 Battery Indicator Lamp
    5. Sony SRS XB43 Battery Indicator Light, How to Read

Other Posts About the Sony SRS XB21

    1. Sony SRS XB21 Factory Reset Instructions
    2. How to Connect Sony SRS XB21 to iPhone
    3. Sony SRS XB21 Buttons Explained
    4. How to Turn Off the XB21 Bluetooth Speaker
    5. Telling if This Speaker is Charging

References for Sony SRS XB21 Battery Indicator

    1. Sony SRS XB 21 Official Product Page at

Revision History

    • 2021-10-14: First published.