Well, I screwed up I think. My bike is a 2011 FLHTK, about 9 months old now. Came back from a ride and cleaned the bike 3 weeks ago, put the dust cover on the bike with the battery tender plugged in - it appears I left the ignition in the accessory position. Must have, because when I took the cover off yesterday that is where the switch was

Anyway, despite the tender being plugged in the battery was dead as a doornail. Absolutely nothing.

Turned the switch off access and tried the tender - the lights on it show that the battery is not taking a charge.

Checked all the fuses, including the inline fuse for the battery tender, all OK. Confirmed on the wifes bike that the battery tender was working. No problem, but on mine it doesn't work at all.

Next step, opened up the seat and hooked a regular charger directly to the battery terminals - the regular battery charger says the battery isn't charging.

Any thoughts? Is this likely a dead short on the battery itself and the battery needs to be replaced?

Will leaving the ignition on like that cause the battery to go so dead that it won't take a charge?

 

You solved it. I like to use 10 amps for 15mins then (if needed boost to 50amps) Just to start her up! 2 amp is better for 8 hrs.

 

Stop !

A dead battery can stress the charging system and blow it up.

don't get a jump and then try to use the bike to charge it


smart:

remove the battery, charge on the bench with a real charger, the best you can do is to charge for 48 hours or so at 5 to 10 amps.

when removing the battery pull the neg cable first

when installing neg cable last ( that way no sparks if you ground the wrench when tightening the positive)

be aware that a charging battery produces hydrogen- no smokes, no sparks

( and the same when connecting charger to battery, so the pos can't spark in an area full of hydrogen gas

also a battery that has been fully discharged will loose 50% of it's rated capacity , at least.

so you may be good for awhile, but think a new battery is in your future...maybe find a deka dealer in bellingham or somewhere close, about $90 USD


Mike

 

Yes, why a real battery charger come in to the picture.

What BLOWS ups? stator? regulator? gas tank? Fuse? I hope not battery!

 

As mkguitar said remove the battery from the motorcycle. Trying to charge the battery with the cables still connected can cause numerous/expensive problems to Your electrical systems.

 

That would be the battery! Kaboom

 

Thanks guys. Did take the battery out, on the bench, regular charger on it. Charger shows it is still not taking any charge at all. Taking the battery in to the dealer tomorrow to see if they will warranty it.

I have had dead batteries before in cars and on bikes, but never have had one that when it went flat because of something left on it wouldn't take any charge? That is a bit surprising to me - and why I am thinking the battery got some kind of dead short in it from the total rundown?

anyway, thanks for the feedback, still feel like a dolt.

 

Hold up!!!!
As strange as it sounds you need to put another battery in parallel (just like jumping it) and then charge them both. AGM batteries will not take a charge if they are dead as a door nail without doing this. Charge with a charger for a few hours then finish charging on its own.

 

Here is a link to the Optima battey site explaining the problem and how to go about charging a deeply discharged AGM Battery.

http://www.optimabatteries.com/produ...agmbattery.php

 

Thats right...don't know why...maybe the smart charger tag the battery as shorted. So yeah.....I've got a few AGM batteries and low to dead ones (daughter and wife leaving lights on) need a parallel connected decently charged battery. I have one of the 2/10/15 smart chargers that can desulfate.