Picture of the glowing red light on the JBL Flip 4 speaker.

JBL Flip 4 Red Light Stays On, Won’t Turn Off

Many JBL speakers, including the Flip 4, have a light that glows or blinks red when the battery is almost out of power. In the case of the Flip 4 speaker, we see this lamp in the battery gauge on the button panel. But sometimes, this red light stays on or blinks for long periods as you play the speaker.  E.g. It starts flashing during play and does not stop, even when you connect a charger.  Thus in this post, we offer reasons that this can occur, and give possible fixes for this typical problem.

Why JBL Flip 4 Red Light Stays On

It’s normal that the battery gauge gives off a blinking red light when the battery drains to very low power reserves.  But this light should change from red to white when you connect the Flip 4 to a properly working charger, and battery recharging begins.

Picture of the glowing red light on the JBL Flip 4 speaker.
The glowing red light on the JBL Flip 4 speaker.

Normally, this meter only glows white, and the number of lamps that glow tells you how full the battery is. It can appear as follows.

Picture of the JBL Flip 4 battery charge status meter, showing the speaker charging.
JBL Flip 4 battery charge status meter, showing the speaker charging.

Or, if the speaker is OFF when charging starts, and you don’t turn it ON during charging, then once recharging finishes, all lights in this meter go out. See this in the next picture.

Picture of the JBL Flip 4 wireless speaker, top view, showing speaker controls, horizontal.
JBL Flip 4 wireless speaker, top view, showing speaker controls, horizontal.

But if the red light does not change to white when you plug the charger into the speaker, then several things might cause this. We list these below thus.

1.The Power Outlet May Not Be Live

The Problem

The AC or car adapter for the JBL Flip 4 may not deliver any power because it is not receiving any to begin with. This can happen due to a broken AC or car circuit, tripped circuit breaker, blown fuse, faulty wiring, power loss, and the like.

The Fix

Check that your outlet has power by testing it by plugging in a lamp or other device, and assuring that that device works correctly.  Reset circuit breakers if tripped, and if the outlet has a light switch that controls it, then be sure that that switch is in the ON position.

2. Power Supply is Malfunctioning or Too Small

The Problem

The JBL Flip 4 red light might continues blinking maybe because the AC or car adapter you have provides SOME but not ENOUGH charging current, even though its getting the correct power input. Its output energy can fall over time. So it might not deliver the correct amount presently.  Please note that this speaker requires 1 amp of charging current at 5 volts (5 watts) from the supply to fully recharge in the specified time of 3.5 hours.

The Fix

The solution is to replace the adapter. We suggest chargers from Key Power, Belkin, and Anker, that deliver at least 1 amp USB power (5 watts) for this speaker.

3. The USB Charging Cable is Too Long, Too Thin, or is Broken

The Problem

The USB cable can limit the charging current too much, even if your power supply is working well.  This might happen with very long or thin cables.

The Fix

To resolve this, use as short a cord as workable. Or, upgrade to a thicker, higher current cable. We advise keeping cable lengths to six feet or shorter, and to select a cable that is certified to carry at least 2 amps for fastest charging.

4. The Battery in the Flip 4 is Bad

The Problem

As lithium ion batteries grow old, they lose their ability to fully recharge.  Plus, the characteristics of the charging current they draw changes as they age.  Indeed as a battery recharges, it draws less and less current. But in the case of battery failure, it may draw too much or too little amperage for the expected charge rate. Therefore, this can confuse the battery management circuits into behaving like no charging is occuring.  So, the red lamp stays on (keeps flashing).

The Fix

To stop this, install a new battery. Keep in mind though, that you can’t easily get to the battery pack in the JBL Flip 4. Indeed, swapping the battery means that you must take the speaker apart.

But note that disassembling the Flip 4 breaks the water resistant seal.  Thus the speaker will no longer be protected if you get it wet, unless of course you can re-seal it when putting it back together.

Breaking this seal may also change the sound quality too. So get a technician to change the battery who knows how to choose the correct replacement. They should also have the skill and sealing compounds to restore the seal to as it was, as they reassemble the speaker. A good battery should fit well inside and provide 3.7 volts and at least 3,000 mAh (11.1 watt-hours). But we suggest using only JBL certified battery units in this speaker.

5. The Speaker Might be Defective when the JBL Flip 4 Red Light Stays On

The Problem

Even if you have a sufficiently big power supply, and cable with a working battery, the charging current that actually gets to the speaker may be too low or too high.  This can happen when the battery management circuits inside the Flip 4 fail, or the battery itself develops a short.  Note that these systems read the battery status, and shut off the charging current when they sense that the battery is full.

But when these components fail, the battery might get no power at all.  Thus, it never recharges.  Again, in this case, the red light might never turn off even with the charger attached. You may also see that the speaker doesn’t play as long before going dead. Or it might not play at all, except when you’re charging it.

The Fix

The best solution here, given the relatively low cost of the JBL Flip 4, is simply to get a new Bluetooth speaker.  Moreover, the circuit boards in this model are quite small.  So unless you can replace them yourself, or know someone who will do it for you, just purchase another speaker to save yourself many headaches.

Other Posts About the JBL Flip 4 Speaker

  1. JBL Flip 4 Picture Gallery for this Portable Speaker
  2. Updating Firmware on JBL Flip 4
  3. How to Reset JBL Flip 4 Bluetooth Speaker
  4. JBL Flip 4 Change Name, How to Rename This Speaker
  5. Finding JBL Flip 4 Firmware Version

Related Posts to JBL Flip 4 Red Light Stays On

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  2. How to Fix when JBL Charge 3 Red Light Stays On
  3. JBL Speaker Red Light Stays On, Won’t Turn Off
  4. JBL Go 2 Red Light Stays ON, Won’t Turn OFF

References for JBL Flip 4 Red Light Stays On

  1. JBL Flip 4 Official Product Page at JBL.com
  2. Where to Buy the JBL Flip 4

Revision History

  • 2022-07-24: First posted.