Picture of the Wonderboom 1 and Wonderboom 2 Speakers Side By Side

Wonderboom 2 Not Charging, How to Fix

Most Ultimate Ears Bluetooth speakers, including the Wonderboom 2, offer truly portable operation via their lithium ion batteries inside. And when said battery dies, you can recharge the speaker with an AC or car adapter. Sometimes though, you may notice that the Wonderboom 2 is not charging fully, or at all, even when you connect the adapter to power, and then to the speaker.  To solve that, we’re here to help.

How to Tell that the Wonderboom 2 is Not Charging

Among the ways you can tell that the Wonderboom 2 speaker is not charging, is by reading the battery status lamp on the top of the speaker in the Power button.  Now this light changes from white and begins pulsing red during play, to alert you that the battery is running low on power.

However, there’s a problem if this blinking keeps going, even when you attach the charger.  Why?  Because the lamp should change at this point, to a soft flashing white, when you apply charging power.  But if it keeps blinking red, then correct recharging is likely not happening.

You can also feel your AC adapter’s surfaces ten or fifteen minutes into the charge cycle.  At that time, it should feel somewhat warm.  But if you detect no heating, then again, the Wonderboom 2 is likely not charging.

Moreover, this light normally shows battery recharging status.  I.e. As long as charging continues, this lamp also continues a slowly waxing and waning dim to bright and bright to dim white light.  And this light either changes to solid white or goes out when charging completes.  But if that lamp continues the recharge pulse pattern after several hours on the charge, then chances are, the recharging is not going well.

Thus when you notice that the speaker is not charging, even though it should be, you’ll want to figure out what’s wrong and how to get it to charge again.  So in this post, we offer reasons why the Wonderboom 2 speaker may not charge when you connect it to power.  Then we give tried and true fixes for this typical problem.





Wonderboom 2 Not Charging, Reasons and Fixes

As we stated earlier, it’s normal that the power status lamp pulses red when the battery inside is almost depleted of energy.  But again, the light should switch to a throbbing white light when you connect the speaker to the charger, and the charger to a power outlet, and battery recharging starts.

Front top view of the Wonderboom 2 speaker, showing the red light highlighted.
Front top view of the Wonderboom 2 speaker, showing the red light highlighted.

Normally though, this lamp only glows or flashes white.  It can look as follows.

Top view of the speaker, powered ON, with its -Power-button lit.
Top view of the speaker, powered ON, with its -Power-button lit.

Or, if the speaker is OFF when charging starts, and you don’t turn it ON during charging, then once recharging finishes, the status light in the Power button goes dark. See this in the next picture.

Picture of the dark -Power- button.
The dark -Power- button.

If the light does not change to the throbbing white pulsating pattern when you plug the charger into the speaker, then several things might cause this. We list these below thus.

1.The AC Outlet May Not Have Voltage

The Problem

The AC or car adapter for the Wonderboom 2 may not output any power due to not receiving any to begin with. This can happen in a defective AC or car circuit, tripped breaker, blown fuse, faulty wiring, power failure, and the like.

The Fix

Check that your receptacle has electricity by plugging in a test light or other device.  Then, reset circuit breakers if tripped. Also, if the outlet has a light switch that controls it, then be certain that that switch is in the ON position.  Or, simply try a different outlet.

2. The Power Adapter is Broken

The Problem

The Wonderboom 2 not charging can also happen because the power supply is providing SOME but not FULL amperage to recharge the speaker all the way, even though its getting the correct power input from the outlet.

Now as adapters age, their output energy can fall over time. So this adapter might not deliver the correct amount if it is ancient.   Thus you may see the lamp do the pulsing recharge pattern, but never turn back to solid white or never go dark. Please note that this speaker needs 0.5 amps at 5 volts from the adapter to fully recharge in the specified time of 2.6 hours.  However, recharging will likely not go as fast as we plan if the charger does not deliver on these requirements.

Picture of the back of the Wonderboom 2, showing its micro USB charge port.
Back of the Wonderboom 2, showing its micro USB charge port.

The Fix

The solution is to replace the adapter, preferably one that has a USB-A plug and delivers up to 5 volts at 1 amp (5 watts). Most common USB power supplies meet these power specs… even the very cheap ones.





3. The Battery in the Wonderboom 2 is Faulty

The Problem

As lithium ion batteries age, they lose their ability to fully recharge, and the characteristics of the charging current they draw, changes as they get older.  Normally, as a battery charges, it draws less and less charge current as it fills. But in the case of cell failure, it may draw too many or too few amps, thus confusing the charging circuits into behaving like no charging is occurring.  So the status lamp shows that charging is not happening, either by never stopping its pulsating white pattern,  or never starting that pattern in the first place.

The Fix

To repair this, replace the battery. But realize that you can’t easily get the old one out of the Wonderboom 2 speaker. Indeed, changing the battery means that you must take this unit apart, and this is an intricate undertaking.

Also note that doing this likely breaks the moisture seal.  So the Wonderboom  2 will no longer be safe to use, should you expose it to water afterwards.

Breaking this seal may alter the sound quality as well. So get someone to replace the battery who knows how to pick the right replacement. They should also be able to restore the seal to as it was, as they reassemble the speaker. A good battery should fit well inside the unit. But we suggest using only JBL certified batteries for this particular speaker.

4. The Speaker Might be Defective when the Wonderboom 2 Is Not Charging

The Problem

Even if you have the proper power supply, with a working battery in the speaker, the charging current that actually gets to the battery may be too low or too high.  This can occur when the battery management circuits inside the Wonderboom 2 fail.  Note that these systems read the battery status, and cut off the charging current when they surmise that the battery is full.

But when they go haywire, the battery might see no power at all though the charger itself is fine.  Thus, the speaker never charges.  Again, in this case, the status lamp might never stop fading in and out, even with the charger connected. You may also see that the Wonderboom 2 doesn’t play as long before dying, if at all, until you connect the charger. Or it might not play at all.

The Fix

The best answer here, is simply to get a new speaker.  Why?  Because the electronics in this unit are quite small.  So unless you can replace the system board(s) yourself, just buy another speaker to save yourself a ton of aggravation.

Other Posts About the Wonderboom 2 Speaker

    1. Wonderboom 2 Buttons Codes Functions Combinations
    2. How to Connect This Speaker to Alexa Echo Devices
    3. Wonderboom 2 Firmware Update Procedure
    4. Recharging Directions
    5. How to Tell if Wonderboom 2 is Charging

References for Wonderboom 2 Not Charging

    1. Wonderboom 2 Official Support Page at UltimateEars.com
    2. Where to Buy the Wonderboom 2 Speaker