Ryobi 40v battery shows full charge with fuel gauge and when connected to a volt meter but when placed in the tool it does not work, also have tried other tools want work in those eather

Question moved to a Ryobi category from MISC.

If they both show charged, they are unlikely to be incorrect. You can test the contacts of the batteries with a test meter, and you can also test the charger output.

If they don't work in a tool, the tool may have failed. Having said that, they do appear to have some history of this. Check out the videos.

https://www.google.com/search?q=Ryobi+18+volt+charger+shows+fully+charged

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Question edited to add FULL make model (what it is).
Category moved from Washing Machines to Ryobi Trimmer.

Replace the spark plug. Strip and clean the carburetor. Replace the fuel with fresh. But hang on though, the RY40002 is electric and runs with a 40 volt battery, so no spark plug and carburetor! :>D Replace the battery, lubricate everything from the motor to the head. Check the motor with nothing attached to it. The carbon brushes may need replacing or its bearings need greasing.

Ryobi RY40002 40V Power Head and RY15523A Expand-It ...

https://www.walmart.com > ... > All Trimmers and Edgers

Includes (1) RY40002 40V Power Head and (1) RY15523A Expand-It Trimmer Attachment · Compatible with All Ryobi 40V Lithium-Ion Batteries (Sold Separately) ...
US$119.90 · ‎Out of stock

Are the battery connections on your machine clean or burnt?
Also something could be burnt out

either battery is charged or battery is bad.
All chargers act different so I can't tell you. Try measuring the battery voltage with a meter. I assume you do not have another battery to try.
If the voltage is about 40V then the device might be bad. If it is much less (discharged) then the charger might be bad.
But the battery may also be bad.
A high internal resistance on the battery might cause the charger to think the battery is charged because it isn't drawing much current

Do you mean the Ryobi 40V X-head cordless string trimmer? This model has a 12-15" cutting width. For the 40V battery, you remove it by pressing and holding the latch button at the bottom of the battery (on the side closest to you). Then pull the battery out of the power head, exactly reversing how you slid it into place. Do not release the latch button until the battery slide free of the tool. The latch is usually stiff and takes a lot of force to hold down. See Fig 4 for the position of the latch in the manual: https://images.homedepot-static.com/catalog/pdfimages/fa/fab7f50b-d65b-40de-9e1c-5fecce2436f5.pdf . The same directions apply to removing the battery from the Ryobi 40V string trimmer with the fixed head.

For the 18V batteries, there are two latches, one on each side of the battery. Press and hold again. These are so stiff that my mother and I often need someone else take off the battery from any of the Ryobi tools. (We're both about 5' tall and 100 pounds. The tools aren't designed for our proportions.)

I hope this helps.

Cindy Wells

test the battery with DMM-Digital Multi-Tester. when full charge a 36V battery measures 37-38 Volts. if battery is full charge the problem is your electric drill bring it to service center maybe need to replace carbon brush or the motor.

Check the battery with your multimeter. If it reads below 36 volts (or whatever the cutoff point is) it may be damaged. But before you run off and buy a new one, use the multimeter to check the voltage from the charger.

Or borrow a good battery and see how your charger behaves.

that way, you can identify the cause of the problem

Battery is weak. Those lights are really useless...more a marketing gimmick. It almost sounds like it developed a memory...this happens when certain types of batteries are not fully discharged before being placed on the charger. Replace the battery and make sure to follow charging directions for that particular type of battery

If charger is good then the battery is in need of replacement.

For others with the same problem (flashing red light won't go off)...make sure you FIRMLY PUSH the battery down onto the charger and engage the latches. Simply resting the battery on the charger will not work.