JBL Partybox 300 Won’t Turn On? – Complete Fix Guide

Wondering why the JBL Partybox 300 won’t turn on? Stay with us to learn more!

The JBL Partybox is a massive Bluetooth speaker that users take the most advantage of when used outside.

The light effects create a remarkable experience but only when the device is working and in this guide, we’ll unwrap the reason why you can’t turn it on.

Let’s learn more!

The Party box JBL 300 is not turning off due to multiple factors including the voltage of the battery, a potential software glitch, or a faulty hardware component. For now, we’ll exclude the faulty circuit board and attempt everything we can to turn on the machine.

Let’s first review the potential causes that could prevent the JBL Partybox 300 from turning on!

My JBL Partybox 300 Won’t Turn On – Why?

As we’ve already mentioned, there could be quite a few different causes that can make your JBL Partybox 300 unresponsive and off.

To be able to start the device we first need to learn what’s making the JBL Partybox shut down and why it’s not turning on easily.

There are quite a few different reasons why JBL Partybox 300 can’t be turned on:

• Temporal Issue/Button Problem
• Low JBL Partybox Battery (0%)
• JBL 300 Partybox Software Glitch
• Non-Working Charging Equipment
• Faulty Charging Electrical Outlet
• Faulty Hardware (Circuit Board)

Yes, there are quite a few different possibilities why the JBL Partybox is not turning on and in this guide, we’ve managed to find a working solution.

However, give the power button one last press to see if the device will turn on, and if not, proceed with the solution guide below!

How To Fix When JBL Partybox 300 Won’t Turn ON?

Solving the problem requires the reader to follow the steps in the guide and simultaneously work on the JBL Partybox 300.

In addition, it’s important to follow the solutions in chronological order to be able not only to solve the problem but also to prevent the party-killer from appearing again!

Let’s jump into the troubleshooting:

Solution #1 Power Cycle The JBL Partybox 300

The very first step is to perform a Power Cycle on the JBL Partybox 300.

The process is simple and you only need to plug the speaker into the outlet and disconnect the machine shortly after.

In case you’re unfamiliar with how to discharge a battery-operated device, follow the steps:

1. Connect the JBL Partybox to the Power Outlet.
2. Press and hold the Power Button for 30 seconds.
3. Disconnect the JBL Partybox from the wall.
4. Press and hold the Power Button for another 30 seconds.
5. Connect the speaker to the outlet.
6. Press the Power Button once to turn on the JBL Partybox 300.

In case the device still does not respond when you press the Power button, perhaps something else is causing the problem.

Let’s continue to troubleshoot until we discover the culprit.

Solution #2 Switch The Power Source!

The next most important aspect of this guide is to unplug the JBL Partybox 300 from the current power source and try a different one.

It’s important to remove any power dividers from the power supply of the speaker and connect the JBL Partybox directly to the outlet.

We understand that these large speakers are usually connected via a power extender so you can power the device in your backyard without worrying about the battery.

Yes, but you need to be confident that the outlet is actually working, specially before continuing further in the guide.

In case the speaker does not respond even when connected, keep reading!

Important: Test the outlet with another device before plugging in your JBL Partybox 300!

Solution #3 Fully Charge The JBL Partybox

In case the basic troubleshooting didn’t help so far, there is one more thing that we can try before taking any technical steps.

Simply, wait…

• Plug your JBL Partybox into a working outlet for at least 3 hours!

We understand that you want to solve the problem quickly, but sometimes the reason behind this fuss is the battery.

When it reaches 0%, you’ll need to definitely connect the speaker to the power, and how long it would take before it can finally turn on, we can’t tell.

Tip: Press the Power button every 15 minutes to see when the speaker will turn on!

Solution #4 Factory Reset The JBL Speaker

Unfortunately, if nothing helped so far we need to execute the good old Factory Reset!

This is the ultimate solution and has proven that most people experiencing the same problem with the JBL Partybox 300.

The reason we did not include this right at the start is that this process will reset ALL JBL settings to default and revert any of the configurations you did.

Here’s how to Factory Reset JBL Partybox 300 in easy steps:

1. Connect the JBL Partybox 300 to the Power Outlet.
2. Press and hold the Play + Volume Up buttons.
3. Keep holding for at least 20 seconds!
4. Press the Power button once.

The JBL Partybox 300 would require at least 2 minutes to reset so be patient even if the device does not make any indication of the operation.

Hopefully, in a few short moments, the device will turn on as well as the LED battery indicator. In case it doesn’t keep reading!

Tip: Re-attempt the steps at least twice to make sure that the reset has been started!

Solution #5 Replace The Battery

This one is not going to be cheap. The JBL Partybox 300 VHBW rechargeable battery costs about $100 but the replacement can’t get any easier. 

When you open your speaker you would notice that the battery simply plugs into the port, so the purchase is the only barrier.

To replace the battery of your JBL Partybox 300 at home, here are the steps:

1. Remove the orange protectors above the screws.
2. Took apart the covers (4 x Philips screws on all corners).
3. Undo the 3 x screws on top to lift the top cover.
4. This will expose the circuit board (optional).
5. On the back of the speaker, undo 4 x screws on the battery cover.
6. Remove the battery cover to expose the batteries.
7. Gently take the battery pack out by pulling on the wires.
8. Then you can unplug and plug in your new battery.

With the new battery, you shouldn’t experience any of the power ON/OFF problems and the JBL Partybox should now be working well.

In case the speaker still won’t turn on, keep reading!

Solution #6 Inspect/Replace Charging Equipment

When the JBL Partybox 300 will not turn on, regardless of what you’re attempting, there is one last important factor to pay attention to.

The battery might be working well, but whenever the charging equipment goes out of order, we can really charge and turn on the device.

Alert: Do not use the JBL Partybox 300 of a damaged power charger!

If you have noticed that the battery started to require too long to charge, shortly before the JBL Partybox went off, it’s highly possible that the charger is faulty.

You need to thoroughly inspect the adapter as well as the connector on the speaker’s end.

Need a New Charging Cable?

We strongly recommend getting a replacement charger 2 Prong Power Cord for JBL Partybox 300. The charger is cheap and effective so make sure to do so before drawing any conclusions in regard to the speaker’s hardware.

Need More Help?

In case you’ve attempted all of the solutions in this guide but nothing managed to help, you would need to check your product’s warranty.

Then you can contact JBL Customer Service and report the problem you’re experiencing as well as what you’ve already attempted.

They will handle the troubleshooting form from there on and the issue will be gone in minutes!

Read Next: JBL Link Music Bluetooth Pairing Not Working?

Quick Recap:

Hence the JBL Partybox 300 won’t turn on because the battery is dead and the charging equipment or power outlet can’t deliver electricity. In case that’s not the problem, power cycle the speaker and perform a factory reset to be able to turn the device on.

We hope that this guide was helpful and informational and that now you can turn on your JBL Partybox 300. If you’re looking for more relevant content, check out our blog.

Good luck!