I was given a Greenworks 25292 cordless mower and a pair of Li-Ion batteries + charger, but the mower does not work. I charged the batteries before trying, so the question is if the problem is with the mower or with the batteries. Each battery has 4 contacts and I tried measuring voltage between each pair using a multimeter. For most pairings I got 0, for one of them I got a number around 13. Does this mean that both batteries are bad? Did I measure correctly? Can a battery like this be tested using a multimeter? Thx!
How can I test a 40v Li-Ion battery for a Greenworks 25292 cordless mower?
- Thread starter ilyaz
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Not sure if you have the manual and if not here you go:
http://www.greenworkstools.com/uploads/documents/25223_gw_19in_40V_LITHIUM_mower_E_manual.pdf
It says to fully charge the batteries before use and that the battery charger will tell you is the battery is bad. If you have a local battery shop near by you might take the batteries to them and let them test them.
Tom
http://www.greenworkstools.com/uploads/documents/25223_gw_19in_40V_LITHIUM_mower_E_manual.pdf
It says to fully charge the batteries before use and that the battery charger will tell you is the battery is bad. If you have a local battery shop near by you might take the batteries to them and let them test them.
Tom
MowerMike
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That mower uses the Gen1 40 volt battery that is wired in a rather strange way. You cannot measure the total voltage between any two points on the battery terminals. Instead, a fully charged battery should measure approximately 24 volts between terminals C and + and between terminals Omega and +. Since you are only getting about 13 volts, the battery is probably not properly charged. When you depress the test button on the battery, how many green LEDs do you see ? All four LEDs should illuminate when the battery is fully charged. If both batteries will not charge, then the problem could be with the charger.
Thanks for the info.
Yes, all 4 LEDs light up on both batteries with the test button is pressed. So that suggests "fully charged"
However, I measured the voltages one more time. For both batteries, I got about 14v between C and + and about 15v between Omega and +. So "not fully charged" or "defective"?
I have a feeling that even if they are not fully charged, the mower should have shown at least some signs of life when turned on. There was none so maybe the switch or the safety key is defective. I'll tinker with it when I have a chance.
MowerMike
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Are you aware that to start the mower you must first press and hold the button on the handlebar, and then pull back on the bail bar ? Do you feel any resistance on the bail bar when you pull it back ? Also, the actual switch is located inside the deck housing, and the cable from the handlebar might not be connected properly to actuate it.
ilyaz,
Adding to what Mike said do you have the "key" that you insert in the battery holder? Look at the owner's manual and you can see what is needed.
Tom
Adding to what Mike said do you have the "key" that you insert in the battery holder? Look at the owner's manual and you can see what is needed.
Tom
Looks like it's working but the pull cable seems to be a bit loose. Maybe that's why it was not starting before. Which is good news. Bad news is that the batteries don't hold much juice, the mower often stops even on short grass and needs to be restarted. It might be time to invest in a new mower...
1 Lucky Texan
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you probably have is sorted now, but a common problem on the twinforce was the bracket at the deck-end of the cable being bent. maybe check there.
MowerMike
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Speaking of cable problems, they've done away with the cable and remote switch on the new digipro brushless version of this mower, and relocated the switch up on the handlebar start button assembly with a conventional two lead electrical wire connected to the motor housing. The wire is protected by a large plastic flexible conduit to prevent damage when the handlebar is folded for storage. Along with the elimination of the unnecessary safety key, the new mower is a lot simpler and more reliable.
Not sure if reviving this thread is against rules, but the follow-up is on exactly the same topic. So almost exactly 2 years to the date, I now have another dead 25292. The battery is showing as fully charged. When I measure voltage between + and C, I get about 18v. When I measure between + and Omega, I see about 18v displayed for the first fraction of a second and then the voltmeter shows "1.". Does it mean the battery is bad? Just like with the one 2 years ago, when I tried to use the mower with this battery, it shows no signs of life at all, like there is no battery in it at all. Thx