Flex chargers have many more unique patterns than some other chargers I’ve covered so far. Those patterns can be confusing to understand as a newer user.
Read this guide on the meanings of Flex battery charger lights to help with that! I’ll list each possible pattern below and show what they look like, along with their meanings.
Explaining The Meanings of Flex Battery Charger Lights
Before I start, I want to mention that the particular Flex chargers I’m talking about are for the 24v Flex batteries. These have two lights on their left side.
Instead of having separate functions, the two lights work together to form patterns. That’s why there are a lot of different possibilities, which makes things confusing.
With that said, here’s a list of each and every single one of those possibilities. Keep reading to learn more about them and what it means when you see each one.
- One Blinking Green Light on Flex Charger
The first light on the list is the most common one. I figure most of you already know about this one, since it shows up any time you put a battery on the Flex charger.
The reason for that is that a single blinking green light is simply a charging indicator. Whenever you see the pattern from the image below, your battery is charging fine.
The bottom light will keep blinking while the other one remains off. It’ll stay that way until the battery reaches a certain percentage, or you take it off the charger.
- One Solid and One Blinking Green Light on FLEX Charger
Time for one of the more unique light patterns on the FLEX charger. This one involves both of the lights, with one staying on and the other blinking, both in green.
This combination of lights starts to show up when the battery currently on charge reaches 80%. Here’s a picture showing what it will look like when that happens:
The one on the bottom will stay solid green while the one above will blink. The FLEX charger will stay in this pattern until the battery reaches full power.
- Two Solid Green Lights on FLEX Charger
The last of the green lights is a pattern that involves both indicators shining solid green. It’s also the last “normal” indicator on these chargers.
Two solid green lights mean that charging is now complete. This is what it looks like when your battery reaches 100% power on a FLEX charger.
- Single Solid Red Light on FLEX Charger
Red is never a good sign when it comes to FLEX chargers. Especially when there’s only one solid red light shining on the indicators, which signals serious issues.
One solid red light is a result of overheating or overcooling. Take your battery out immediately after seeing the light from the photo below to avoid damage.
Overheating (or even overcooling) is awful for the battery. It can cause the cells to die out completely and if you put the battery on charge, it could lead to thermal runaway.
In other words, it might cause a fire or an explosion because of the drastic temperatures. Remove the battery ASAP to avoid anything like that.
Once you remove the battery, set it aside for a few hours before trying to charge it again. Leaving it overnight should be enough for it to come back to normal and charge normally.
- Single Blinking Red Light on FLEX Charger
I think the worst out of any light is the single blinking red light. That’s because this light shows up when the FLEX charger detects a bad battery on itself.
Here’s an image of this final pattern to show you what it looks like:
Sometimes the light may be a false alarm because of dirty contact points. But, if cleaning them doesn’t make the light go away, it’s likely you need a new FLEX battery.
I have recorded a video to show you how to fix this issue if the Flex 24V battery is not charging.
