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Battery Tender Light Staying Red

36967 Views 21 Replies 17 Participants Last post by  stilup
Hey guys,
After doing a search in the Battery Tender threads, I didn't find any answers, so I got to pick you brains here. Was not able to ride at all this past summer, left the bike parked/covered in the garage and stupid me, I did not have the battery tender hooked up. After not starting it for several months, when I tried it last week, battery stone cold dead. Hooked it up to idling car via jumper cables for several minutes to get some charge, prior to jump starting with said car.
It started right up, rode that day for over 100 miles (mostly highway), without shutting if off, volt meter reading 14 volts the whole time & I was not using radio, or any accessories.
Got home, shut it down, it starts right up. Left it overnight on battery tender, light still red in am. It started right up, rode it again the next day, no problems, reading 14 volts, starts right after I shut it several times. Tender has been hooked up continuously for several days now without the light turning green. Tried a different tender, same result.
Battery and bike are only two years old, with less than 7k miles.
Anyone have any ideas why the tender light is not turning green? I would have to imagine that the battery is fully charged by now.
Thanks in advance for your replies.
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A battery can be strong enough to start a healthy motor without being fully charged. It may be getting weak and can't take a full charge.
Automotive type batteries will discharge over time, for any number of reasons. Sadly today age has nothing to do with it. They will take a charge from a jump as you indicated. With the help of the alternator you will keep the vehicle running, and can often restart it. I'm surprised it started the next day, but hey take what you get. As far as the Tender goes I believe it won't turn green until it's fully charged (which is obviously what you're looking for) or it's up to 80%, meaning the Tender can't get it there. I know cold weather is coming for you but for reliability, probably buy another batt. Someone else will maybe give more insight. hope this helps.
I bought a new Ultra Limited and the battery had a bad cell in just over a month. My tender wouldn't go green either. Had to warranty replace the battery.
Take the battery to a local auto parts store or dealer, whichever is closest, and have it load tested.
Will confirm or rule it out as the problem.
Batteries are subject to going "Bad" at anytime. No real reason to it, just how it is . :)
Not a battery expert myself, so just repeating what others have said. Once a battery goes completely flat it never recovers full capacity again. It may well have gone from a 27 amp hour battery to, say, an 18 amp hour battery. It will now behave like a much smaller battery from now on. Many get more time, but some batteries have had the course in 2 years anyway. If your bike still starts after it sits for a week, you might get the rest of this season out of the battery, but start saving for a replacement.
I'd replace it now before it takes out your alternator & or the regulator
To make the tender work right it has to be plugged into the bike first then the wall..
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To make the tender work right it has to be plugged into the bike first then the wall..
When I first got a BT, maybe 4 or so years ago, I remember reading to first plug into the bike then to plug into the wall outlet. And I have always done that. Glad to know I actually did something right for a change.
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Even a blind hog will find an acorn once in a while.
...once a battery does drain to 0 volts, it may not be possible to re-charge it at all. My "big" charger analyzer will indicate "btty unable to accept charge"...

I was referred to this place for a battery. Good prices for OEM battery, free shipping and two day delivery!

Buy a new gel battery and put the battery tender on it while it is sitting and you will receive years of service. Almost had 5 years on my last RK battery.
I think if 2 different tenders stay red, there is a problem with the battery. It's not fully charging and the regulator and gen/alt are staying on all the time.

Invest in a replacement bat. I just got a Big Crank from Battery Mart. Perfect fit. $89 delivered in 3 days.

Your battery will strand you somewhere.
Battery mart is $100 now, but the ThrottleX I got is $9 more. Both US made and have free shipping. Take your old one to the recycle place and get a few $$ for it.
Try cleaning the battery tender terminals at the battery and the connector first before buying new battery, could be just a weak connection.
He can clean all he wants and it will not do any good. His battery is almost 100% sure to have a dead cell after being neglected for many months. It is more than likley a wet cell battery and it will not take a charge if left on the battery tender for months. As I posted earlier, Buy a glass mat type of battery for great service and life. There is no maintance, no adding water and they hold a charge for months. They may be turned on their side with no problems. If you leave them off charge for 5 months, I've still been able to start the bike. I'm not advising that as I use my battery tender all the time but these batteries are much stronger that the old lead plate batteries.
:thumbsupThanks for all the replies and input. Many pointed out the fact that the battery was not accepting a full charge, that's what I was thinking originally. I did a load test, and it showed the battery was on the border line. I brought it back to the dealer where I bought it, they checked it, and found the same. Only problem was that the bike was about 3 weeks out of the two year factory warranty, and of course the Harley- Davidson extended warranty I have doesn't cover batteries. However, they did the right thing and warrantied the battery (Thank You TY). Now all is good!
If you guys are ever in New Windsor, NY, stop into Moroney's Cycles and say hello. Good People-They do right by their customers, and great deals on new models.
BTW, while I was there, we noticed that my rear tire was looking a little bald, so I bit the bullet for new sneakers front & rear- Michelin Commander-2's. I've read a lot of good things about them, so we'll see how they do...
To make the tender work right it has to be plugged into the bike first then the wall..
It does not matter been using tenders now over 20 yrs and always have unplugged the vehicles leaving the tenders plugged into 120v once return plug tenders back on vehicles. A few of our tenders are near 20 yrs old.
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