As a DIY enthusiast I have a lot of batteries on my hand and to handle them I use the Battery Tender. It’s a low voltage charger used on batteries to keep its voltage healthy and make sure that it doesn’t lose its charge over time.
It is because if batteries are not being used they can deplete themselves and can turn bad if not in regular use. But since I am using this Battery Tender I am always confused to see different lights as I don’t know the meaning behind them.
This time I was flashed with a red and green light, it was a new light code for me and it only seemed like a problem to me. This is where I decided to look for its meaning on the internet and here is what I found.
By the way, I also have a short video about this topic and you can watch it below first before you continue reading this article.
This normally means reverse polarity. To fix this, just connect the positive to positive and negative to negative correctly. But if the polarity is correct and it’s still showing green and red, it means the battery could have develop internal short circuit.
Battery Tender Flashing Red and Green: What It Means and What You Need to Do
The red and green flashing light code means that the battery is not being charged due to not being hooked up to the battery properly or the prongs are connected in a reverse polarity, although I did put the battery in the correct order.
I made sure to connect the battery from positive to positive and negative to negative but the light still kept flashing red and green.
If you also connected your battery in the right order and you are still being bothered with this light code it simply means that the battery has developed an internal short circuit and may have reversed its polarity by itself.
When this happens the Battery Tender thinks that the battery is connected in the wrong way and throws the red and green flashing light.
To make sure I tried charging my 12V battery using the same Battery Tender and it immediately turned solid red which meant it was charging properly.
I even tried testing the dead battery with a battery tester and the results were as expected, it showed me nothing which meant the battery was dead.
A healthy battery should show its internal voltage but this dead battery showed me nothing, there was no voltage at all.
Related: How I Troubleshooted My Battery Tender Red Light Flashing or Yellow
This is where I concluded the research and found the problem, the battery had either developed an internal short circuit or was too dead to even charge it.
Related: Why Your Battery Tender Red Light Stays On & Won’t Go Off: Reason
If you also face this problem and your Battery Tender keeps flashing red and green light on you, only replacing the battery can fix the problem for you.
