Is your Ryobi 40V battery not charging? We have some good news for you: it is possible to fix many common Ryobi 40V battery problems yourself.
The Ryobi 40V ecosystem offers a fantastic combination of power and convenience for a huge range of yard tools, from mowers to leaf blowers. However, this convenience comes with a significant investment, as replacement batteries are certainly not cheap.
When a battery fails to charge, often signaled by the frustrating flashing red and green lights, the thought of buying an expensive replacement can be daunting. The good news is that many of these issues are diagnosable and repairable.
This guide moves beyond simple fixes to address the full spectrum of failures, from basic user errors to complex internal faults.
Let’s take a look at the most common Ryobi 40V battery problems and how to fix them.
Ryobi 40V Battery Diagnosis Wizard
Use our specially built wizard below to quickly diagnose your 40v battery problem. Continue reading the article for more in depth information.
Ryobi 40V Battery Wizard
Let’s find out why your battery isn’t charging. We’ll start with some essential pre-checks.
Essential Safety Warning
Li-ion batteries store massive energy and can trigger thermal runaway—a deadly chain reaction causing fires, toxic gases, and explosions.
Never attempt repairs if you see swelling, hear hissing, smell chemicals, feel excessive heat, or see smoke.
Critical triggers: Physical damage, short circuits, overcharging, extreme heat.
Required safety gear:
- Safety goggles
- chemical-resistant gloves
- well-ventilated workspace
- Class ABC/D fire extinguisher
- dry sand nearby.
Never use water on Li-ion fires.
If you can’t meet these conditions, buy a new battery instead.
Foundational Diagnostics: Is It the Battery, the Charger, or Something Else?
Before assuming a complicated internal fault, a careful check over can often identify a simpler issue. Many charging problems are caused by the charger, dirty contacts, or temperature…
Not the battery itself.
1. Systematic Charger and Terminal Inspection
The physical connection between the battery and charger is a common failure point.
- Inspect the Contacts: Examine the metal contact blades on both the battery and the charger. They should be clean, straight, and free of damage or corrosion.
- Cleaning Procedure: If the terminals are dirty, use a cotton swab lightly dampened with high-purity (>90%) isopropyl alcohol to wipe them clean. For light corrosion, you can gently use a small piece of fine-grit sandpaper (600 grit or higher) or a fiberglass scratch pen on the contacts, followed by another wipe with alcohol to remove any debris.
2. Is Your Battery Too Hot of Too Cold?
Li-ion batteries are very sensitive to temperature. The internal Battery Management System (BMS) will prevent charging if the battery is outside its safe operational window, which is generally between 32°F and 113°F (0°C to 45°C).
- Too Cold: Attempting to charge a battery below freezing can cause an irreversible process called “lithium plating,” which permanently reduces capacity and increases risk. If your battery has been in a cold garage, bring it inside and let it acclimate to room temperature for at least one to two hours before charging.
- Too Hot: Charging a battery immediately after heavy use (e.g., mowing the lawn on a summer day) accelerates chemical degradation and shortens its lifespan. Let a hot battery rest in a cool, shaded area for 30 to 60 minutes before placing it on the charger. Do not place a hot battery in a refrigerator or freezer, as this can cause condensation and internal moisture problems.
3. Faulty Ryobi Battery Charger
Testing if the charger itself is faulty can be tricky. Ryobi 40v chargers have sensors that prevent them from outputting voltage unless a battery is detected, so you can’t simply test the output with a multimeter.
First, try a simple power cycle. Unplug the charger from the wall, wait a full minute, and plug it back in. This can sometimes resolve temporary electronic glitches.
If that doesn’t work, the best way to test the charger is with a second battery or a second charger.
- Use Another Battery: Try charging a known-healthy 40V Ryobi battery. If it fails to charge and gives the same error, your charger is likely the problem. If the second battery charges correctly, your charger is fine, and the original battery is the issue.
- Try Another Charger: Plug your battery into a known-working Ryobi charger. If it still fails to charge, your battery is confirmed to be faulty. If it charges up properly, your original charger is the problem.
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Understanding the Ryobi Charger Light Codes
The LED lights on your charger are your primary diagnostic tool.
The “Testing” mode is especially important, it is not an error. It means the charger is actively conditioning a battery that is too hot, too cold, or too deeply discharged.
Be patient and allow the charger time to complete this process.
| Red LED Status | Green LED Status | Orange LED Status | Charger Diagnosis | Detailed Explanation | Recommended User Action |
| ON | OFF | OFF | Power On / Standby | The charger is plugged into an AC outlet and is ready. No battery is inserted. | Insert a 40V battery to begin charging. |
| OFF | Flashing | OFF | Charging | The charger is in the primary charging phase. This is normal operation. | Allow the battery to charge until the green light becomes solid. |
| OFF | SOLID | OFF | Charging Complete | The battery is fully charged and in maintenance mode. | Remove the battery from the charger for use or storage. |
| Flashing | Flashing | OFF | Defective Battery | The charger has detected a critical fault like a short circuit or severe cell imbalance. | Attempt deep discharge recovery methods below. If unsuccessful, the battery may be permanently failed. |
| OFF | OFF | Flashing/Solid | Testing – Hot Battery | The battery’s temperature is above the safe charging limit (approx. 113°F). | Remove the battery. Let it rest in a cool, shaded area for 30-60 minutes before retrying. |
| OFF | OFF | Flashing/Solid | Testing – Cold Battery | The battery’s temperature is below the safe charging limit (approx. 32°F). | Remove the battery. Bring it indoors to warm to room temperature for 1-2 hours before retrying. |
| OFF | OFF | Flashing/Solid | Testing – Deeply Discharged | The battery’s voltage is too low for normal charging. The charger is trying to revive it. | Leave the battery on the charger. If it doesn’t switch to “Charging” (flashing green) after 30-60 minutes, proceed to manual recovery. |
Ryobi a “Sleeping” Battery: Deep Discharge Recovery
The most common reason for the flashing red and green lights is a battery in “sleep mode.” This happens when a battery is over-discharged, and its voltage drops so low that the charger’s safety circuits refuse to recognize it. Our goal is to manually raise the battery’s voltage just enough for the charger to accept it again.
Method 1: The Patience Method (Micro-Charging)
This is the safest and simplest method, but it requires patience.
- Plug your charger into a power outlet.
- Insert the sleeping battery into the charger just long enough for the indicator light to appear (1-2 seconds).
- Immediately remove the battery before the red and green lights begin to flash.
- Wait a few seconds, and then repeat the process.
- Continue this cycle for up to 30 minutes. Each time, the charger delivers a tiny pre-charge current, slowly “walking” the battery’s voltage up until the charger recognizes it and begins a normal charge cycle.
Also Read: Ryobi Pressure Washer Troubleshooting
Method 2: The Peer Jump-Start
This method uses a healthy, charged Ryobi 40V battery to jump-start the sleeping one. It is faster but carries more risk if done incorrectly.
- You will need a healthy, fully charged Ryobi 40V battery and some insulated wire (speaker wire with insulated alligator clips is recommended).
- Identify the positive (+) and negative (-) terminals on both batteries.
- CRITICAL STEP: Connect the positive (+) terminal of the healthy battery to the positive (+) terminal of the sleeping battery.
- CRITICAL STEP: Connect the negative (-) terminal of the healthy battery to the negative (-) terminal of the sleeping battery.
- DOUBLE-CHECK POLARITY. Reversing this connection will cause a dangerous short circuit.
- Leave the batteries connected for 10-15 minutes.
- Disconnect the wires and immediately place the revived battery on its charger.
Warning: Experts advise against boosting Li-ion batteries that have been deeply discharged for a long time (a week or more). Microscopic structures called dendrites can form inside, creating a latent short-circuit risk when current is reintroduced.
Use a DC Power Supply To Jump Start Your 40V Battery
This is the most precise and safest manual method, but it requires a lab-style variable DC power supply.
You will need:
- A DC power supply capable of outputting 40 volts DC
- Some wire – standard speaker wire or similar will do the job
- Set the power supply’s output voltage to 40V.
- CRITICAL SAFETY STEP: Set the power supply’s current limit to a very low value, like 200mA to 500mA (0.2A to 0.5A). This prevents a dangerous rush of current into the battery.
- With the power supply on, connect its leads to the battery terminals, ensuring correct polarity.
- Monitor the voltage on the power supply’s display as it slowly climbs.
- Once the battery voltage reaches about 34V to 36V, disconnect the power supply and place the battery on its standard Ryobi charger.
This method is essentially the same as using a second battery, but instead we use a DC power supply set at the same output voltage (40v)
Advanced Internal Repair (When External Fixes Fail)
If the above methods fail, the problem is likely internal. This process carries significantly higher risks, and the safety protocols outlined at the beginning of this article must be followed strictly.
Disassembly and BMS Reset
You will need a Torx Security screwdriver (size TR10 or T10H) and plastic pry tools.
- Remove the four (or more) Torx screws holding the case together. You may need to cut the Ryobi sticker along the seam of the case.
- Gently use plastic pry tools to separate the case halves, releasing the internal clips.
- Once open, you will see the battery cells and the “brain” of the battery—the Battery Management System (BMS) circuit board.
- Sometimes, the BMS can be reset by momentarily shorting two specific pins on the circuit board with a small piece of insulated wire. This can clear a “soft fault.” The correct pins vary by model.
| Battery Model Number | Reset Pins to Short | Notes / Location Description |
| OP40501, OP40401 | RST and GND | The pins are clearly labeled. RST is a single pin, and GND is a nearby ground pad. |
| OP40602 | RESET and GND | The pins are located on a header on the board and are labeled. |
| OP40404 | RES and GND | The reset pin is labeled RES. It should be shorted to a nearby ground (GND) pad. |
A Critical Warning: The “Un-resettable” Modern Battery
A major change in newer Ryobi batteries (roughly post-2021 models) has rendered the simple reset procedure obsolete.
When these more sophisticated BMS units detect a severe fault, they can log a permanent fault. To prevent unsafe repairs, the BMS locks itself down and may be programmed to deliberately drain the entire pack to zero volts, making revival impossible.
If you have a newer battery and the reset procedure fails, it has likely entered this permanent, unfixable state by design. Further attempts are unfortunately not possible.
Is The Battery Too Old?
Unfortunately, it could simply be that your Ryobi tool’s 40-volt lithium-ion battery is simply getting old.
Typically, a Ryobi battery or any 40-volt lithium-ion battery maintains its performance for two to three years, or approximately 300 to 500 charge cycles.
One charge cycle describes the timeline between completely charging the battery, utilizing it until it’s fully discharged, and then charging it up once more.
Once your Ryobi 40-volt battery reaches its third or fourth year, you may begin noticing performance issues.
This could mean the battery’s inability to retain enough charge or, in more serious cases, it might fail to recharge entirely. Should you encounter this situation, replacing the old battery pack with a new one is recommended.
You can purchase a new battery here.
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- Model OP4060A
![[2Pack] 40 Volt Battery for RYOBI 40V Power Tools - Generic](https://m.media-amazon.com/images/I/41SHRdnuqXL._SL500_.jpg)
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Proactive Care: How to Maximize Ryobi Battery Lifespan
The best way to fix a battery problem is to prevent it from happening in the first place.
- Implement a Cool-Down Period: One of the most damaging practices is to take a hot battery from a tool and place it directly on the charger. Always let it cool in the shade for at least 30-60 minutes first.
- Avoid Deep Discharges: Constantly running your battery until the tool dies puts maximum strain on the cell chemistry. It’s far better to swap to a fresh battery when you notice a drop in power or the gauge hits one bar.
- Smart Storage is Key (The 40% Rule): For any storage period longer than a few weeks (like over winter), store the battery at a 30% to 50% charge level. This usually corresponds to two lit bars on the fuel gauge. Storing a battery at 100% (especially in the heat) causes rapid capacity loss, while storing it at 0% risks it entering the problematic “sleep mode.”
- Climate Control: Store batteries in a cool, dry place, ideally between 50°F and 77°F (10°C and 25°C). Avoid unheated garages in winter and hot sheds in summer.
- Remove When Fully Charged: While chargers have protections, it’s best practice to remove the battery once it’s full to avoid minor heat buildup and stress on the cells.
Buying a Replacement 40V Battery
When a battery is truly beyond repair, you’ll need a new one.
- The Aftermarket Gamble: The low prices of third-party batteries on sites like Amazon can be tempting, but it’s a market filled with risk. Many use low-grade cells that can’t handle the power demands of a tool, have fake capacity ratings, and may lack critical safety features, creating a serious fire risk. It is strongly recommended to buy genuine OEM Ryobi batteries or those from highly reputable aftermarket brands.
- Market Comparison:
- Ryobi: Offers the best versatility with over 85 tools in the 40V line, making it ideal for homeowners who want one battery system for everything.
- DeWalt: A professional-grade brand built for job site durability. Their FlexVolt batteries are backward-compatible with their 20V MAX tools, offering great value for existing DeWalt users.
- EGO: A specialist in high-performance outdoor power equipment. Often the leader in power and runtime for lawn tools, but their system isn’t as broad as Ryobi’s.
You can purchase genuine Ryobi batteries and chargers from online retailers like Amazon or locally at Ryobi dealers.
Frequently Asked Questions
Can a Ryobi cordless tool battery be repaired?
Yes, you can repair a Ryobi cordless battery. But, it might take too much time and effort.
Opening up the batteries can be difficult; depending on what part is faulty, it may be quite expensive to fix.
Remember that batteries can be dangerous, so it’s best to get a qualified technician to check the battery for you.
Is it OK to leave a Ryobi Lithium-Ion Battery On The Charger?
No, you should charge the battery after use until it is full, then remove it from the charger and store it in an area that doesn’t get too hot or cold.
The ideal battery storage temperature is around 59℉, but standard room temperature is usually fine.
I’m also at a loss for removing the battery from the trimmer. Any ideas appreciated. Thanks
Hi George, If you tell me the model no. I can look into it for you.
Mine seems to be stuck like that at times. Press in the release button all the way and PULL HARD.
We solved this by having one person depress the button and pull, while another person pushes the battery out.
I am having trouble removing the battery from my Ryobi weed cutter. It seemed to be stuck.
Any ideas? hank you.
I’m having the same problem. I cannot release the battery. Is it the release button??
It’s hard. Press the button on the battery and hold it in, then pull on the battery and in the opposite direction, pull on the tool.
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?
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.
Did you try to methods in the article?
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.
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.
Did you contact Ryobi? Warranty repair?
1st and 3rd diode light on battery and charger flashes red/green together when on charger.
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.
after trying fix option 3 my charger is flashing red and green without the battery. How can correct this?
It be that you just have a faulty battery and it cannot be revived.
Thank you so much. I appreciate your feedback, Aaron.
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.
Hi Tom, I am not sure sorry. Best bet is to give the manufacturer a call and find out.
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.
Its probably a dead battery. 4 years is pretty good out of a battery these days!
Have a trimmer. When I put battery in charger the flashing red light appears. What should I do?
Have you tried the fixes in the article?
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.
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.
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.
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 ?
Thanks.
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
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?
My battery mower goes on but cuts out any suggestions on what to do
Not really enough info there to help out. Does the battery go flat when the mower cuts out? Is it charging correctly?
Go to Youtube and search “Ryobi lawnmower shuts off fix”
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!
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?
Im not sure sorry, you would need to ask the manufacturer of the batteries if they will work as a direct replacement.
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.
Ciao!