How To Fix Common Ryobi 40v Battery Problems

In my opinion Ryobi 40V cordless tools are some of the best available, although it does seem that the batteries can suffer from numerous problems. Replacement batteries are certainly not cheap, and most of us will want to avoid the need to buy a new battery if at all possible.

So I have some good news for you; it is possible to fix most Ryobi 40V battery problems yourself.

Let’s take a look at the most common Ryobi 40V battery problems and how to fix them.

Disclosure: As an Amazon Associate I earn from qualifying purchases. However, this does not impact our reviews and comparisons. All opinions are our own we pride ourselves on keeping our articles fair and balanced. For more info see our disclosure statement.

ryobi 40v battery problems


Ryobi 40V Charger Red And Green Lights Flashing

Whether you have a Ryobi cordless mower, a pole saw or one of the many other tools available, a common problem with Ryobi batteries is when the charger shows green and red flashing lights.

Well don’t panic yet because it isn’t always a sign that your battery needs replacing.

There are ways to attempt to fix this problem; take a look at the possible fixes below.


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Battery Entered Sleep Mode

battery sleep mode

The most common cause for your Ryobi 40V Charger showing flashing red and green lights is that the battery has been over-discharged.

This is commonly known as the battery being in “sleep mode”

What this means is the battery has been discharged to such a low level that the charger has trouble detecting if the battery is healthy or not and decides to not risk charging it – showing the dreaded flashing red and green lights.

The problem here with Ryobi 40V chargers, is that they don’t incorporate a “boost” feature that would allow a a battery that has entered sleep mode to be woken up again.

How to fix this (maybe);

As with any DIY fix with cordless tool batteries – it does have some dangers involved. Battery university recommends not boosting batteries that have been in sleep mode for a week or longer.

So keep this in mind when carrying out the following recommendations.

There are two ways to try and wake up a sleeping battery.

The Fix Option 1:

ryobi battery fix

Use a second healthy, fully charged battery of the same voltage and connect the terminals matching polarity (positive-positive, negative-negative) using wires and leave them connected for a few minutes.

Then try charging the battery again – this may be enough to kick the battery back into life. You can see a video guide on how to do this here.

The Fix Option 2:

Use a DC power supply set at the same voltage as the battery and connect the positive output to the positive battery terminal and the negative output to the negative battery terminal.

Once again, leave this connected for a few minutes then try charging the battery.

The Fix Option 3:

This method should only be used if you don’t have a spare battery or power supply as per option 1.

Patience is required here – so read these instructions carefully and find somewhere comfortable to sit!

  1. Connect you charger to the power outlet
  2. Place the battery in the charger until the green indicator goes solid
  3. Just before the red/green lights start flashing, remove the battery from the charger
  4. Re-insert the battery into the charger again and repeat steps 2-3
  5. Do this until the green light flashes constantly (might take up to 30 minutes)

Why does this work? Well each time you insert the battery into the charger, it gives it a small amount of charge before detecting the battery as sleeping.

ryobi battery problems

So repeating this process over and over results in the battery slowly being charged in very small increments each time.

Eventually, this results in enough charge for the battery charger to resume normal charging operation.

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Battery Too Hot or Cold

So while we all love the Li-Ion technology of modern day batteries, it does have some problems that older styles of battery didnt have to worry about.

One of these being the narrower range of temperatures that they will operate, and charge in:

Li-Ion batteries will generally charge between 32°F to 113°F (0°C to 45°C).

So, the first thing to check if you are having problems with your Ryobi batteries is if they are indeed too hot or too cold.

If it is exceptionally cold where you usually store/charge your batteries, bring them inside and let them warm up to room temperature and then try charging them again.

If it is a hot day, or you have been using your batteries already and they are quite hot, try throwing them in the fridge, or taking them to a cooler area for a short amount of time before trying to charge them again.

Corroded or Dirty Battery Terminals

If the metal contacts on the battery or charger become dirty or corroded, then it can cause the Ryobi charger to incorrectly assume that the battery is faulty.

If your terminals are corroded, then the corrosion can be removed with a piece of sand paper.

Dirt on the terminals can be removed with a wire brush or an alcohol-soaked wipe.

Sometimes getting to the actual terminals can be difficult due to them being recessed, if this is the case you will need to try different tools or items to reach them for cleaning purposes.

What If None Of These Solutions Work?

Unfortunately, if none of these solutions solve your Ryobi 40V battery problems then it is likely you have one of two problems: Either your battery is faulty, or your charger is faulty.

Here is what you can do next:

The best way to test which is the faulty part, is to take your battery down to your local store that sells Ryobi 40V tools and try it on one of their chargers. If the same fault occurs then you have a faulty battery, if the problem does not happen on a different charger then it is likely a faulty battery charger.

If you want to ask my advice directly, feel free to send me an email at aaron (at) or leave a comment below and I will do what I can to help. Be sure to tell me your model numbers of your batteries/chargers etc so I can give the most relevant advice.

Alternatively, use the contact form here or ask in our Facebook group.

Where Can I Buy Replacement Parts?

If you need your replacement Ryobi 40V battery parts in a hurry, then you will want to head straight down to the closest supplier and buy it locally.

If you aren’t in too much of a rush and are looking to save some cash, then consider purchasing from a reputable online store such as Amazon.

Click here to see Amazon’s selection of Ryobi 40V Batteries and Chargers.

Are Non-Genuine Ryobi Parts Available?

Yes, they are! Some are great and work well, others are not worth the time or the money.

Here is our list of recommended non-genuine parts:

Best Value

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About The Author

Aaron is the founder of and Essential Home and Garden. He likes to spend his spare time with his family, and doing DIY projects in the home and garden.

241 thoughts on “How To Fix Common Ryobi 40v Battery Problems”

  1. You were right. It took a lot of patience (a good 15 minutes), but worth the time inserting and removing the 40 volt battery. Finally the green charging light stayed on and battery is charging. Will comment on the end result. Thanks a bunch!

  2. I’ve just encountered the Red/green light flashing for my 36V 5Ah battery and am balking at the fact
    that these cost more than the appliance to replace. It has 2 “charge light dot” visible when looking at the charge of the battery, but only one “charge light dot” when in the appliance (lawnmower in this case.)
    Voltage measured between +ve and -ve terminals :33.9V
    Voltage measured between +ve and T1 :32.6

    I’m going to try your recovery method (they’re Li ion, so the procedure should be the same) but I was
    wondering if you know if the 36V tools will support a 40V battery.

    Will keep you posted if the “wakeup” process worked.

  3. Option 3 worked for me. Battery had 12.5V. A reasonable shown voltage can be a over-discharge battery. I put the battery on and off the charge about 20 times. The green light starting flashing constantly and continued to fully charge. The battery works as expected.

  4. I have a issue with one of my 40 volt Ryobi Batteries. It shows as fully charged but when it’s used in only runs the tools for a few minutes and then quits. If you wait about a minute it will start working again. Still showing full charge. It does this over and over. Any suggestions?

    • I have similar problems with a few 40v batteries I own. They charge fine and if I used the on a low draw system they work fine, but as soon as I put one in my lawn mower or weed whacker they run for a few minutes… stop… then a minute or two later then start up again.

      Not an overheating problem as the batteries do not get hot.. seems like a current issue.

    • Do you have another battery to try in the tool? It might be the tool. My 40v weed whacker does that when using the edger if it gets overtaxed. My guess is that there is something wrong with the tool.

  5. I have had two of my batteries get stuck in my lawn mower over the last two weeks, and I think it’s a common problem that I’ve seen other people in the comments mention.

    Upon further inspection what I’ve discovered is that the plastic fins near the terminals of the battery have been warped, as if the battery overheated while in use. They still hold a charge, but they are now incredibly hard to get into and out of any of my tools or chargers.

  6. My 40 volt lawnmower is cutting out with a battery level over half. It is warm outside, but is it a possibility I need a new battery

    • I had a similar issue. Are you using the bag? The reason I ask is because I discovered the bag, when full, jumped out of the connection slot every time I turned the mower around. Took a while to figure it out but flat I discovered it.

  7. They all flash at the same time four times.
    Also the battery is nos accepting any charge.
    When you put it on the charger the red and green light flashes on the charger.

  8. I bought a Ryobi OP4026 40v battery, charger, and a couple of weed eaters at a yard sale. I planned on using the motors and battery for some robotics projects. The battery was dead when I got it so I put it on charge. It charged all the way up before giving me the red/green flashing lights. I put the battery in the weed eater and nothing happened. So I hooked one of the motors directly to the battery leads, nothing again. I hooked a multimeter to the battery leads and the voltage slowly drops as the battery slowly drains itself. Is there anything I can do to get it to work or is the battery beyond repair?

    • Replace the FET on the heatsink. I only get 21 Volts at the output. The main board has 42 volts. Put it apart and charge each bank with 4.1 Volts. Remember polarity of batteries as lithium ion will blow up if reverse charged. Don’t do this if not comfortable with electronic. I take no responsibility for take risks with lithium batteries . Stay safe.

  9. Dear, in France it is called 36V (instead of 40V) but I suppose it is same. Charger using 230VAC for Fast or Slow speed (depend on model). I want to charge my battery using an inverter and small solar panel. Also I need to reduce that charging power (currently 80W – even 300W on fast charger not to modify). 40W should be perfect even if that take more time to fill. I think it is easy to modify inside charger (a resistance value or something else), to reduce output power. Did you already experience this or are you interested in if I find ?
    Best regards.

  10. I purchased the generic battery and the mower will run fine for about 30 seconds and then it shuts off. I release the bar, push the start button and it starts up again. Each time I get 30 seconds before it shuts off. Did this for about 30 minutes while cutting the lawn several times. Battery shows levels of charging as I would expect. Any thoughts?


      • I had same problem with generic batteries in my Ryobi mower, runs for less than a minute and cuts off. If I pull battery out and put back in it runs for less than a minute again and repeat. Replacement generic battery did same thing. Ended up Just using those batteries in other tools

  11. What if the battery or the charger got wet. But neither were plugged in at the time. I tried drying the battery out in the sun but no luck getting it to charge

  12. Aaron,
    I’d used the refrigerator option a couple of times in the past to get the temperature in range. This time it did not work. In our home, the highest DC supply I could find was 18V. Hence, I tried your Option 3, pushing the battery into the charger for five green flashes, out, five green flashes, out, and so on. It took about seven minutes of this until…voila! I have a working battery and charger again. Thank you, thank you, thank you.

    • Not only did option 3 work for me on my 40V Ryobi but it also worked on my 18V milwaukee red lithium! I’m so stoked! The Milwaukee had been dead for at least a year and wouldn’t take charge but now its perfectly fine! Thanks for your help!

  13. Fix option 1 does not show underneath the 40 volt batteries the positive and negative wires hook up. Please explain as I see no terminals.

  14. My 40v batteries fuel gauge stopped working a week or so ago. Now a week later when the battery is placed in the charger the light stays solid green and never flashes. When I test the battery in the trimmer it works for 2 to 5 seconds and then dies??? My spare battery functions normally in the trimmer and chars fine. Any suggestions?

  15. Hello,

    I have a 40 volt 5 ah Ryobi battery. It just stopped working this week when i was trimming my grass with the trimmer. The trimmer is not defective as I tried a spare battery and the trimmer works. When we try charging the
    defective battery it charges normally, the green light flashes green until it is fully charged and all the lights on the battery com on when you press the button on the battery. The voltage on the battery only reads 27volts from the + to the – terminal on the battery. When I took the battery apart and measured on the board from the CL1- soldered connection to the Bat+ terminal connection on the board, I measure 41volts. Seems like it is charged but its not getting to the battery out put terminal. Any ideas?

    • I have a couple of these batteries that are faulty. when I disassembled them all but one had some blue green corrosion on both the top and bottom of several connection points on the board. You may have the same problem. On the top you can get to it to remove but there are several rather large solder connections that you will have to unsolder in order to get remove the board to get to the bottom of it. If you have access to a Pace solder station or something similar you can get the board removed but otherwise…..?

  16. I press and hold the “?” Button on my battery, all four lights flash twice, pause, then flash twice again. The battery doesn’t charge nor does it work in the trimmer. I put it in the charger, all I get is the red power on light.

    • This question was also asked in our facebook group, but I will post the answer here as well for others to benefit:

      Hi Matthew, it sounds to me like a faulty battery. But you can’t be sure without trying another battery that you know is working.
      Did you try the methods of waking a sleeping battery? Do you have a multimeter so you can see what the voltage the battery is at?

  17. Hello I’ve got a Ryobi 40v battery that has been great up until lately it shows all green on the battery but dead in the leave blower. I tried all options but none worked. Is there a chance for recovery. I tried in another charger but it did the same thing. Shows all green but will not work.

  18. I did contact Ryobi – as well as a local Ryobi dealer; local dealer said I had a dead battery. Still doesn’t make sense logically – but am going with their recommendation to replace battery. I was told my existing battery is still under warranty – I will pursue a replacement as well.

  19. I purchased a Ryobi cordless weed eater last year (I’m small so the model I selected works for my female/small build). When it came time to do yard work (April) the charger worked fine. Then I re-plugged it in and the SOLID RED light came on and stayed. I assumed it needed a replacement, so in May this year, I bought a new charger/battery. So here I am 2 months later, the new charger is doing the same thing (SOLID RED) which is the indicator for “defective”. I find it odd and am tired of purchasing a charger every 2 months. Thoughts on what to do (aside from throwing more money against this equipment?). If I’m forced to buy another charger, I’ll have spend more $$ on chargers than the equipment alone. Frustrated.

  20. Has anyone had this issue?
    I put my 2.6Ah battery in the charger and it flashed green and finally solid green. It never registered on the light display at the end of the battery regarding how much had charged. When it went to solid green I took the battery out of the charger and pressed the button at the end of the battery to indicate how much charge it has and it doesn’t display anything at all. I tried to put it in a tool and nothing happens. I then tried to put it back into the charger and it goes straight to solid green. What can be done?

    • Yes David we have a OP40261 2.6Ah battery doing exactly what you say. We also have a second OP40261 battery functioning normally. Note that the bad one will not work in our 40 volt hedge trimmer, but does operate in the 40 volt blower.
      On the bad battery, the green status lights do not function at all anymore.

    • I have this exact same problem. with my 40v battery. It didn’t even flash green, just went to solid green right away with no indication on the end of the battery that it’s charged and when put into the weed eater…didn’t run. Thanks.

  21. Hi Aaron,

    As you suspected my OP4026 40v lithium-ion battery is faulty (around 4 year old), I replace it with a new fully charged 40V4.0AH but the trimmer/edger is still not working. This points to the tool itself is the problem. May be the switch, just guessing. Will the repair be covered under the 5-year warranty ? Thanks.

  22. My Ryobi trimmer/edger stopped working. The 40 volt lithium-ion shown fully charged (press the ? button on the back and all 4 lights shown green). Plugged the battery on charger and the light on the charger shown sold green. What could be the problem ? The battery will be 4 year old in 3 weeks. Thanks.

  23. I had a similar issue. There is a red button between the Handel and base of Handel on right side. If the Handel slides off the button the mower cuts out. Try using a star bit to tighten up the handle connection.

  24. I used option #3 to fix my battery’s sleep mode. I did take about 30 minutes, (a little less), but it did. Nice job saved me the cost a new battery.

  25. I have a Royobi 40402 40V blower. the symptoms are it starts fine blows for a minute or two then stops.
    If I release the trigger, and tap the outlet or remove and replace the battery it will start but only runs for 30 seconds or so.
    I felt it might be the switch since it got so hot, so I did buy a new switch, I have the same problem seems like over heats something then springs back to life when it cools.

    I had the same problem last year with the charger if I left it plugged in while I was out using the tool when I came back the lights would be off.

    I learned to unplug the charger on hot days when I was using the battery after that the tool ran fine.
    BTW this problem was not present last season it started this year. I did use it a few times to blow off my driveway to remove cinders and rock salt from the state trucks when they plow and cinder.

  26. Ive got red/green on two 36V Ryobi batteries.
    I tried option 2 (power supply) to the + and – terminals but no current flows.
    Do i need to make any connectino to the other terminals marked T ?

  27. Hi Aaron,
    I’ve been given a Ryobi trimmer with a #OP4026 battery. If you press the charge indicator on the battery (?), it shows 4 lights as being fully charged. But when put into the charger the red/green lights flash indicating a defective battery. So I tested, ohmed the wiring, switch, and motor of the trimmer with all components testing good. I then checked voltages of the battery as follows:
    + to – = 19.9 volts
    + to T1 = 39.9 volts
    What should the voltage output be between + to – terminals of the battery? It seems to reason to me near 40 volts as it shows fully charged.
    I would appreciate your comments.
    Thanks in advance, Larry Green

  28. I’ve got the blinking red green issue. This is the second season I’m using this mower and I left the battery on charge all winter. Could that be the issue?

    • It’s good practice to remove the batteries from the charger – so it could have caused problems. Have you tried the suggestions in the article?

    • I had this problem too. Assuming your mower is like mine, check the bolts that hold the handle to the mower. On the right side (looking as if you are pushing the mower) at the handle/mower connection, there is a small switch that must be activated to tell the mower the handle is fully set in the “use” position, not the “fold for storage” position. On my mower, the bolt the handle swivels on was loose enough that the switch would vibrate so that the mower thought the handle wasn’t properly positioned for safe operation.

      I tightened the bolts on both sides (added a few drops of blue Locktite to prevent them from coming loose again). Problem solved.

      Hope this helps!

  29. Can I replace my Ryobi 40V battery model OP4026 with a different brand or model no.? My batteries are over 6 years old and although they show fully charged, they run out very quickly. I spoke to Ryobi who told me that 6 years is over the lifespan of the batteries. I want to replace them. Amazon has other batteries such as Ryobi OP4030, or Lasica OP4050A. Would they work in my mower?

    • Hannah,

      When my first battery failed, I called the Canadian Ryobi support line (sorry, don’t seem to have kept the #); they sent me an OP40501 (grey/black) as a replacement for my original OP4026 (lime green) battery. It works fine. Matter of fact, the OP40501 is 5.0aH, so it’s 20% better than the original.

      Also, no questions asked. I just told the dude that answered the phone that one of my two batteries was showing RED/GREEN flashing on charger. Free shipping. And they didn’t want the old one back.


  30. How do I get a batter off a RY4000A1 Weedeater? It says you push the button on the bottom, but it doesn’t move (like doesn’t go in or out) and I can’t get the battery off.

  31. Hi,
    So I have a battery that I am trying to charge from being completely dead, the charging dock is blinking red for testing, and after awhile the battery itself is now blinking on the screen that shows battery power. All of the 4 battery lights blink quickly for 5 times then once for a longer amount of time. What does this mean?

  32. I have both a weed whacker and a new drill. The weed whacker is older than the drill, the drill is not even a year since I bought it. I went to use the drill, grabbed the battery from the charger and it didn’t work. So I grabbed the batter from the weed whacker and the drill didn’t work either. So I tried them both in the weed whacker and it didn’t work either. Then when I plugged the batteries back on their chargers, the light blinks just red on both. What in the world does this mean?? Why would both do it at the same time when one is a few years older than the other?

  33. Thank you for your help comments.
    I just pulled out my 10 month old 40v battery lawn mower (April now). The battery has been in the charger since October. Powered up whenever I turn the power bar on with all my other chargers.
    Only one green light on battery. Runs mower for 15 seconds. Put in charger all lights on battery come on, one flashing, and charger green light flashes for a minute then goes solid green—full charge. Remove battery, check lights. One green light. Again 15 seconds of charge.
    Suggestions. (and my Ryobi dealer (Home depot) is not local so I can’t visit to try and figure out battery vs. charger.)
    I have not tried your option 3 yet. though I never get the green/light result…but I will try it next.
    Thanks for any suggestions,

  34. Ok, have a ryobi hedge trimmer, 40v. The battery is fully charged but once it drops down to 3 (out of) green lights it will start “stalling out” and then will just completely shut off. Put it back on the charger to get back to full, start trimming again and it does the same thing. Any ideas?

      • Excellent article. I may end up using some of the tips for a battery I have. I actually have 6 batteries. 3 good, 2 with completely dead cells, and one with good cells and a bad board. I just finished swapping a good board onto the good cells, but the voltage at the contacts is only slowly creeping up, and when a load is applied it drops right off. I’m hoping that a charge cycle will reset it and if not I’ll try something else. Even if it still doesn’t work, these batteries are worth a few bucks for repair on eBay. But hey it was still good soldering practice!

  35. My 4Ah battery three contact post has a badly corroded positive (largest) contact that has gotten hot and has partially melted the plastic so badly that the whole post needs replacement.
    I have removed the hold down screw but need advice on replacing the post (removal mostly).

  36. Thanks for the article.
    When I check the battery gauge, it shows it’s full and flashes. And yes, I’m guilty of leaving it on the charger way too long. I’m also unable to use it.
    I have another one that charges to 2 notches and I can use if for a bit, but when it dies, it still shows 2 notches.

  37. My Ryobi drill battery has always been dead when I pull it out to use it no matter when I fully charged it from steady red to steady green. I’ve tried storing the battery away from the drill, and truedleaving it in the drill. Still dead. Bought new batteries, same result. Do I just leave the battery in the charger all the time?

  38. When I use a voltmeter the charged battery reads approx 38 volts. When it is under load on my leaf blower the battery quickly reads below 10 volts. When not under load the battery reads 38 volts once again. Is this a symptom of old batteries?

  39. I have a 36v 2.6ah Ryobi battery. through ignorance I repeatedly pressed the lever after it first stopped, result is battery works for about 4-5 minutes then stops restarts when I press lever again, eventually stops working. When I place it in the charger there are still 3 solid green lights with the 4th flashing green which goes continuous green eventually, so you have 4 solid green lights, then it goes through the sequence again as described above. Would appreciate any suggestions on how to fix.


  40. I have had to replace my battery ( 40 volt lithium Ryobi ) three times luckily through warranty. They seem to be ok if I take the batteries out right after they are fully charged. If I forget and leave them in the charger for a day or two they don’t work anymore. Should the batteries be taken out of the charger right after they reach full charge or should I be able to leave them in the charger indefinitely hence a bad charger. All batteries were only a few months old and the charger less then a year old. I love the Ryobi grass trimmer but it’s annoying having to remember to remove the battery from the charger. I have 18 volt Dewalt batteries that I have left in the charger for a few weeks with never a problem.

  41. My 40 V Ryobi lithium ion battery is fully charged. When placed in either of my devices it will not work. Previously, are used it in the weedeater and the weedeater got hot. Again, the battery mail takes charge, but will not work.

  42. My 40 volt Ryobi battery is only a couple years old so I went on line to try to see if anyone else has had the red/green flashing kiss of death charging problem which led me to your site. I tried option 3 and it worked. It took at least 35 minutes of connecting and disconnecting the battery but it finally showed a sign that it might be working after about 25 minutes when the green charging light would stay on a little longer before shutting off. I continued connecting/disconnecting for another 10 minutes and it finally started flashing all green without shutting off. It went through a complete charge and now I know not to let the battery completely drain. Thank you very much for this fix that reallyworks.

    • Hi John. Glad it worked for you! You should be able to let your battery completely drain if it is used regularly. A problem occurs when you use it till its empty of charge, then let it sit for some months.

  43. One of my Ryobi 40v lawnmower batteries only works until it is half discharged. And then I can recharge it. It is fairly new (the other battery works fine). They have always been kept inside. How can I get the bottom part of the battery to work?

  44. Hi there!

    When I plug in my Ryobi 40V Lithium Ion battery charger without the battery attached it has a solid red light. I attach battery and it blinks red three times, then blinks green three times, then solid red, then no lights whatsoever. The indicator lights on the battery show depleted charge, but it isn’t completely dead – I used the weed eater briefly, but it had slowed power.

    • Hi Bridgitt, that could be a faulty charger or battery. Sorry I can’t be more specific but it’s hard to tell without testing a few things. I would guess its likely the battery though.

  45. Ryobi 40V battery (96 Wh), 3 years old, will charge. All four lights illuminate after charging. Put battery in mower and will operate for 10-15 minutes. Check battery fuel gauge, 3 lights illuminate. Will not operate mower. What gives with the lights being illuminated but short run time? Has the battery lost capacity? what is a good indicator to recycle this current battery and purchase a replacement?

  46. my battery is a 2016 battery and it will not charge. its not the charger because i have another battery and it charges fine.

  47. My batteries stop functioning after they are only about 60-70$ discharged in my mower, weeder, and edger. Can they be bled down to zero? Seems like a memory issue. When I set them in the charger, they blink with at least 1 light on, sometimes 2……

  48. I don’t get any lights on battery or charger when I plug them in. Is it the charger? The battery still works for a few seconds. The weed eater and blower are only 18 months old and not used much.

  49. My 40volt battery won’t charge. The green light on the charger and battery flash for hours without charging the battery.

  50. My Ryobi battery is ok. Because I had a replacement and tried with that also. The problem is that It cuts off when I first start the thing. It doesn’t stay running. Like I said its not the batteries. This machine is only 1 year old.

  51. The battery lights on the battery do not show up at all and when I put it on the charger it goes to green as if the battery is fully charged. When I put the battery in the trimmer is does not work. Any suggestions?

    • Hi Christine, the manual should tell you how to get it out. If it is a strength issue, then you might need to ask a friend or a neighbor for help? But if you find this is an ongoing issue I would recommend returning it to the store and choosing one that has an easier release mechanism.

  52. I currently have a Ryobi Trimmer Model P117 18 volt which is approximately 6 years old. I have arthritis in my hands and it is very difficult if not impossible to remove the battery from trimmer. Is the Ryobi One + String trimmer 18 volt 13″ String Trimmer / Edger have the same battery or has design changed so it is easier to remove from trimmer?

    • Hi Marlene, I have never considered that before – but I am sure it is a problem that many people face when using these tools!
      Because the severity of arthritis can differ so much from person to person, I would recommend going to your local hardware store and having a look at what they have there. Tell them your problem, and ask them if you can see and try the battery removal process for each model. That way you can be sure to get one that you can actually use!

  53. Hi Aaron, my 40V battery was working fine and then i dropped it about two feet on the pavement. when i went to charge it, my charger light is green but the cells on the battery do not light up. Can dropping the battery cause it to be inoperable?

    • It certainly can! Batteries are quite heavy for their size and they also contain breakable parts (circuit boards, electronic connections, plastic etc). You could try opening the battery houding (just the plastic bit) up to see if you can see anything – but do be very careful as it can be dangerous.

  54. Aaron any idea on a Ryobi 40v hedge trimmer when the battery shows fully charged but the trimmer does nothing at all?
    All 4 green lights on the battery and solid green light on charger. I put in on the trimmer and nothing happens at all.


  55. I have an Ryobi 40 volt string trimmer that is 5 years .code CS1305.
    It charges according to the the charger lights.
    I get to 4 green lights and if I use it it will just stop and when I put it back on the charger it show 3 green lights and charges up to the 4 green light and works for awhile.
    What do you think I should do?

  56. 40v ryobi trimmer: Depressing trigger does not cause trimmer head to turn and no sound. battery charger green light stays on with battery in dock. battery reads 18v dc across terminals. bought new rebuilt charger. same experience. why would battery charger light stay green if battery is defective (only charges to 18 v)?

  57. My OP400 charger repeatedly stops charging after about 15 minutes and all lights go dark. Removing and then replacing the battery does not cause the charger to wake up.
    However unplugging the charger from the 110v for about 30 seconds and then plugging the charger back in, does reset it and it will continue charging for about another 15 minutes. then it shuts down again.
    What can be done to fix this??

  58. my Ryobi trimmer stopped working after the string coiled up twice, jamming in between. recharged the battery and tried again with no results. still not working, any suggestions?

  59. Fantastic, I plugged my battery in and unplugged it 3 times and now it is fully charged.

    How did you know this?

  60. Hi,
    Thank you very much for sharing your insight. I have a 40v Ryobi battery than when plugged into the charger the charger light stays green but the battery doesn’t charge. At this time what can I do? Please help me?

  61. Aaron, thank you, Fix Option #3 worked like charm for my Ryobi 40V. Required about 4-5 minutes of in-and-out but then the green stayed solid and battery is charging. Thanks!

  62. Hey Aaron,
    I have the ryobi mower with 2 batteries. This year I have one battery that won’t work in the mower despite showing its fully charged by the tester. The charger works fine to charge the other battery and the mower works. Any ideas?

  63. Arron my Ryobi charger shows solid red the battery has no charge and the light stays red when i try to use the weed eater it goes for a second then stops then goes the again any suggestions will be nice

    • It sounds like the battery is not being charged – or possibly even that the charger is not detecting that a battery is plugged into it at all.
      This could be a tricky one to diagnose. First thing I would do is clean the terminals on the battery and the charger. The second thing I would do is try to ascertain whether it is the charger or the battery that is faulty. Do you have any other batteries that work in that charger?

  64. Aaron
    I have two Ryobi 40 volt Lith to run a chainsaw, 1 battery shows fully charged both on the charger and on the lights on the battery but will not even try to run the saw, the second battery shows defective on the charger ( red & green Lights flashing) with only one light on on the battery but runs the saw just fine.
    Any idea’s


  65. I bought a 40v weed eater and charged it last night to full. This morning I used it until it quit and tried it again and it quit again so I put it in the charger and got no lights. I left it in for a couple hours and still nothing. Any suggestions?

  66. I have a 40 v mower with 2 batteries about 4 yrs. old one battery works fine the other stops with 1/2 charge showing on the indicator can it be fixed or should i replace it ?

  67. Just bought tjhe ryobi 40v mower and after charging all night, I used the next mor ing and the charged last 10-15 min. I called support, they said thats not normal and to try fully charging 3-4 times and it “should” last longer. It doesnt make sense to me as to why it would make a.difference but I’ll try. Dpes this sound normal to anyone??

  68. Hey this is Sam Peters. I have a battery ryobi trimmer with attachments. I bought a new battery. However when i was outside trimming the yard, the trimmer stopped and then started again. That is even with the battery in and the triggers engaged, it was unresponsive. Then i took the battery out and put it back in and still nothing. Then after a couple of minutes it started working and I was able to get finished. Wondering what it could be?

  69. I bought a Ryobi line trimmer that has a 40V lithium ion battery and charger. I have it plugged in to (re)charge, the “charging” light is pulsing. I don’t think it’s charging because the “charged” light has not come on and it’s been on for several hours.
    Do I have a faulty battery?, faulty charger? This is new equipment purchased a couple of months ago. Should I take it back to the Home Depot where I got it and get a replacement battery or charger?
    Thanks, Sarah.

  70. Hi! My battery has worked great for about 5 years—this year however, I noticed that neither the charger or battery are lighting up when I attach the battery to the charger. The battery held its full charge from the fall and I used it, but now that it died, it won’t recharge. Does that sound like the battery or the charger? I just ordered a new battery online, I’m hoping it wasn’t the charger

    • Hi Sharon, Sorry but it does sound more like a charger issue to me. It seems like the battery has gone completely dead, and because the charger is dead (no lights) the battery won’t work anymore either. Look at the positive side though, you will now have two batteries to use!

  71. An issue with this battery…any advice?
    The battery works to start the mower but once you turn the mower off, if you go to restart the mower you have to pull the battery out and reinstall it for it to work?

  72. Arron,
    Can you tell me what signal the t1 terminal needs to tell the charger to put out the 40 volts? If I connect the ground it goes to defective even though the battery has 39 volts. I’m just trying to get the power supply in the charger to turn on.

    • Hi Vincent, Sorry but I am not sure. I havent currently got any of the devices here to check how they work at the moment. Maybe someone else can help out if they read this.

  73. Is there a way on the charger to bypass the sleep check function?

    Or if I had another charger from a different manufacturer with the correct voltage does anyone know what the electrical connections are inside the battery that need to be connected to.
    I saw one source online that showed the hook up, but it was for a ryobi 40v but the main board inside was constructed different than the board in mine

  74. I habe a 40v ryobi battery than when plugged into the charger the charger light stays green but the battery doesn’t charge nor work in any tool. Can that be fixed

  75. I had the same issue as Larry W. Connections are clean. Continued trying the fix even though the lights were just flashing red & green continuously. Now my charger just flashes red & green even without a battery attached. Any advice?

  76. Hi Aaron, I think you are the expert I should ask my question. I got a Ryobi 36v charger BCL3620S. When the charger is empty and first plugged in, it showed flashing red light ( the manual says it should be steady red light). After I put the battery in, it was still flashing red lihgt and not charging.
    Then I tried plugged in the charger with the battery already in it. This time the flashing red light quickly turned into flashing green light for a couple of seconds than came the alternating red and green light. I had tried option 3 but the battery still couldn’t charge.
    Do you think I got a defective charger or a defective battery?

  77. Aaron you are the expert. I picked up one of these units. When I go to use it it runs around high speed for a few seconds and then completely stops. I put the battery on the charger and it lights up steady green. If I then put it back on the weed eater it will do the same thing. Just runs a few seconds and shuts off

      • I’m not sure of the age. I picked it up second hand. The entire unit, battery and weed eater are both in exceptional condition. I would doubt if it was used more than once or twice. Is there a date code anywhere?

        Two other things I’ve noticed. First, the battery indicator on the battery does not work. Second, if I run the weed eater at a slower speed, it will run quite awhile. By ower speed ,I mean somewhere between half power and full power

  78. Hi Aaron, I have a Ryobi cordless drill, I don’t use it often and it won’t charge it just continues to flash red? does this mean it is stuffed? I have never dropped this drill and it is still in mint condition but I think it would be out of warranty? help

  79. I tried method three, and all it did was ruin my charger. Now the charger flashes red and green as soon as it’s plugged in, without even having a battery mounted on it. Is there a fix for this?

    • Hi Larry,

      The only thing that I can think of is that you have accidentally bumped one of the contacts out of place? Check that the contacts on your charger and battery are clean and look to be where they are meant to be.
      What is the model number of your charger and battery?

  80. I have a 40 volt Ryobi that displays a 100% charge, but only has 19 volts on the terminals. Initially, it had 40 volts across the terminals, and would not power a trimmer, so I assumed the trimmer was bad and replaced it. The new battery works fine in either tool.

    Not sure why it would display 100% charge, and have 40 volts on the terminals, but still not power anything. I am equally unsure why the battery initially showed 100% with 40 volts across the terminals, but now only has 19 volts and still shows 100%.

    Thinking the circuit board must be bad, but interested in your thoughts

  81. When I press the button on the battery all green lights work but go out when button released
    When I place battery on charger red light flashes but no green lights work

  82. I also experienced a battery failure, under warranty, and Ryobi shipped a replacement battery and charger. The new charger didn’t work! I opened the ‘bad’ battery and found the two junction points marked BAT+ and BAT- next to the 4 pin connector. I jumped from the good battery charging terminals, to the defective battery +- terminals (with a spark!). In 1 minute increments, followed by a charge attempt. After 4 minutes I put it in the good charger and it fully charged! So, I have two good batteries and know how to resuscitate them. Good luck!

  83. Good evening. I haven’t used my trimmer since August. Brand new battery in July and the battery was left on the charger in the garage . Garage is not heated and I just went out and saw that the charger was red. I pressed the button on the battery to see if It was fully charged and nothing lit up. I attached It to the trimmer and It did not work obviously because It is not charged. Not sure if the cold has anything to do with it? Any thoughts?

    • Have you got a multimeter to test the battery voltage? I would try bringing the battery charger and battery inside, let it warm to room temperature then try charging again. But it is possible that for some reason the battery has lost all of its charge causing it to enter sleep mode.

  84. Hi, Aaron! I recently purchased a new Ryobi OP4015 40v battery. I’m trying to charge it. 1st the charger was flashing green, & I had 2 lights flashing, then a little while later the charger turned flashing red, & battery went down to 1 cell being charged. I’ve already tried your 3rd option & worked for a while, but could I possibly have a bad charger? It’s what I’m beginning to think. Anyway, could you please give me some insight on what you think it might be? Thank you very much! Alan Brinkman.

    • Hi Alan,

      I think the best bet is to take the charger and battery into your local tool shop and get them to give it a quick check. They should have new chargers in stock to test your battery on to work out which is at fault.
      Otherwise, you might need to contact Ryobi support.

  85. Thanks for sharing your insight.
    I have a brand new battery – never been charged since original purchase at HD on a blower.
    I have two batteries so have had them hooked together as described for over one hour with no results. It has been sitting in my garage for several months, so the idea of “sleeping” makes since but it does not seem to take the charge from the other battery. Have you had any luck contacting Ryobi or is there a warranty on these batteries?

  86. Hello Aaron. I have 2 40 volt ryobi batteries with a similar problem. The first one showed as faulty on the charger. I eventually tried a different charger and it took a charge! I used it one time in my trimmer and charged it. It showed a full charge but wouldn’t work again. It’s showing 19 volts more or less with a volt meter. I have the same symptoms with a battery someone gave me. Lights showing full charge, 19 volts and not working. I left them in the charger several hours just to see if the lights were incorrect but the voltage stayed around 19. A common occurrence? Thanks

    • Have you tried option 3? It is highly possible that your batteries are faulty though. If you want to let me know the model number of your tools/battery I can look up a replacement for you.

  87. So, Aaron. You said if solution #3 wouldn’t work for me, I might have a dead battery, which I assumed I did in the first place. So if that is the case, what’s my answer? Is there no other way to reserrect the battery? Should I keep trying to slide it in & out of the charger until the charger recoginizes the battery? I’m stumped here. Just trying to find a quick fix, so I don’t have to purchase a new or used battery! Thanks, again! Alan Brinkman.

    • It is certainly sounding like you have a dead battery Alan, which unfortunately means replacing it. Send me more details if you like: aaron (at) essentialhomeandgarden dot com and I can help you source what you need.

  88. Hi Ken,
    I have a 40 volt blower and use it to blow fluffy snow off my drive. I have 3 batteries and it takes all three to do my drive and our elderly neighbors too.
    A few days ago I tried to charge one of the batteries and it would not take a charge, thinking it might be too low,due to being cold, I sat it in the house near the register and left it for an hour. When I put it back on charge, it took a charge just fine. Then today I cleared the snow again and following the cleanup, I placed that battery in the charger again, and again, it will not take a charge. The air temp is 18 degrees today, so I did not do the warm up thing again, but maybe tomorrow.
    Can the cells be replaced, making it new again, if this continues to happen?

    • Hi Bill, if your batteries are too hot or cold then they may not take charge until the temperature normalizes. While you can replace the cells in the batteries, the amount of time it takes you, the cost of the cells and not to mention the possible safety implications make this barely worth it.

      I would highly recommend looking for new batteries (non-genuine are fine.) If you are having trouble finding a replacement let me know and I can help find an exact match, but Amazon should have you covered.

  89. I have a P104 lithium battery that shows full charge on both the charger and on the battery, but will not work when placed in any of my Ryobi tools. Any suggestions?

    • Has it got dirty terminals perhaps? You could try testing the output voltage with a multimeter to see if there is voltage present. But that does sound suspiciously like it could be faulty circuitry on the batter control board.
      Otherwise there are some third party batteries on Amazon that are a direct replacement for the P104’s here: By all reports these batteries are just as good as genuine Ryobi’s.

  90. I am trying to determine if I have a bad batteries or a bad charger. When I plug the charger into the wall, the red light comes on. When I plug a battery into the charger, the charger flashes green 6 times, then red, green, red, then the light goes out. The light will not come back on unless I unplug the charger for several minutes then plug it back in.

    Has anyone experienced this? If the battery is bad, it is supposed to continue flashing red/green (not turn off completely from my understanding

  91. since there are no flashing lights, I didn’t think any of the solutions you offered would apply. after trying #3 I still have a battery the charger indicates is ready for use, only to get a second of power from the tool you sent. if this is the quality of your items, I would like to return the tool and get a refund.

  92. Hi, Aaron! I have a bit of a problem. I tried the solution #3, out & in for 30 minutes, but the red & green lights keep flashing. Do I need to do this for a longer period of time? Or what is the actual “key” do doing step 3? I really need to get this battery going, again! Is it possible the battery is frozen inside, & won’t budge? Please try to let me know if you can! Thank you!

    • Hi Alan, Sorry it took me so long to reply. Unfortunately, if fix 3 isn’t working for you then you may just have a dead battery. Is there any reason that you can’t replace the battery? Feel free to email me for a quicker response on admin (@) essentialhomeandgarden DOT com

      • Hi, Aaron! Yes it is possible to replace the battery, I’m trying not to because of the expense. So let me ask you, if my battery is dead, is there no other way to bring it back to life, short of re-building the parts, which I have no knowledge of? Or does it have to be discarded at this point? I use it for my snow blower, which only gets used a few times a year.

        • Hey Alan, unfortunately if you don’t feel like replacing the individual cells and/or the circuit board in the battery then there is no magical way to revive them – apart from those I mentioned in the article.
          Amazon has the new ones, Otherwise if you are looking to save some money then maybe look for second hand units?

  93. I had discovered method 3 myself. I have, however, a different problem. My charger APPEARS to be charging – green lights flashing on both charger and battery – however, the battery is not charging above the current level. I have two chargers and three batteries (multiple Ryobi 40 v. tools.) Two of the batteries have solid green on the first of four lights and flash on the second. The third, flashes on the very first light. Both chargers have the same “manifestations.” This all started after using my leaf blower with all three batteries, and trying to recharge. No previous problems.

  94. Dear Lord, thank you thank you thank you thank you thank you for these tips! The one that requires patience, the last one that you suggest, it works like a charm. And thank God! YOUR WEBSITE JUST SAVED MY BUTT!!! Thank you thank you thank you! Hahaha! I’m thrilled to say the Ryobi is charging now, and truly thanks to you! Praise the Lord!


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