Battery dead quickly? : V-Twin Forum: Harley Davidson Forums

Electric Head · 10-18-2009, 08:22 PM

I rode home from work on Friday, got fuel on the way, all worked fine, parked at home, set alarm, went to go to work today and no alarm light was flashing, so I held fob button to set alarm for 20 seconds or so, nothing, I'm thinking the battery is flat. Is it usual for a battery to go like that, worked perfectly Friday night, nothing on Monday morning.

I haven't tested anything else yet as I didn't want to be wrong and set the alarm off as I'm not to sure how to stop it if it does. Even removing the battery wouldn't stop it right as it has its own backup.

Any input would be appreciated.

hbmc · 10-18-2009, 08:40 PM

your alarm is a draw--it may have its own back up battery---unknown. See manufacturer. If factory see manual. Your battery is not charging reasons are bad ground bad or loose-- cell in battery (load test at dealer) charging system bad. Regulator or Stator not sure of your year. Also connection at stator and regulator (see plug by crank and front cylinder)
Many stop and goes without a good run to actually charge battery the amount used at starts along with lamp and alarm draw. Go to NAPA auto they have a great charger for about 30 bucks easy to alter for battery caddy style that dealer chargers 75. Thereby not having to remove the seat see part number 85-201 12 volt Napa.

Definite to have a battery caddy! You can pop the ends off the Napa and attach them to the posts and the cable it comes with has a quick disconnect. You will see. Need to round ends to solder or crimp on I prefer crimp and solder then liquid tape I am real goofy about elect connects.
\
You should get a 12 volt tester with light on it about 3 bucks and then see your draw with all accessories off. (see specs manual) No manual go get one. Must have will use as long as you have the bike.
Regards

Electric Head · 10-18-2009, 09:08 PM

Thanks for the quick reply hbmc, it's an 06 Fatboy, battery was in there from the showroom, so it sat for a while before I bought it near the end of 06, and is 3 years old. I'll check out the connections you mentioned and the service and user manual when I get time, had to get to work.

I don't really think it is not getting a good ride to charge as I ride 30km to work, 30km back, 20km of which is highway speed 3 to four days per week. Once every 3 rides I fill up, so one extra stop start, for one ride. The bike had absolutely no trouble starting on Friday night, either cold or hot when filling up. That is the only riding I have done on the bike for the last two years.

hbmc · 10-18-2009, 09:29 PM

have it load tested for crank amps---cell might be bad as it is a rather old battery. It does take a good hour to ride and charge the battery though.

Electric Head · 10-18-2009, 09:43 PM

Quote:

Originally Posted by hbmc

have it load tested for crank amps---cell might be bad as it is a rather old battery. It does take a good hour to ride and charge the battery though.

No worries mate, I'll check what you said, get the voltmeter on it, hopefully don't set off the alarm lol and if it's just a battery every 3 years that's ok, would hope for more but that's ok. I was planning on replacing it now anyway, doing my tyres, brake pads, fluid, fork fluid in a week or two, so was going to get a new battery. Then I decided hold off until I do my next service, march / april next year, I guess this probably makes up my mind for me.

Cheers for the help mate!

Electric Head · 10-19-2009, 05:57 AM

Ok I chucked the multi-meter on it in and out of the bike - 5.75V - looks like half the battery shorted or something, exactly half of what it should be without ignition on. All fuses look ok.

Damned alarm wouldn't turn off with the fob, not sure it would have worked entering the code with the bars either, but now the backup battery is flat or it gave up, either way it shut up. I realised I was doing the manual code entry wrong after the alarm stopped - didn't have run-off in off, not mentioned clearly in the owners manual, but is on the wallet card.

Krayven Sumhead · 10-19-2009, 07:22 AM

Both of my scoots drained the battery with the alarm set. I no longer set the alarms when they are parked in my garage. My batteries stopped going dead.

Electric Head · 10-19-2009, 11:36 PM

Yeh I used to do that for a while, locked the steering head and ignition only and might go back to that.

hbmc · 10-20-2009, 02:03 AM

i remember when I had an alarm put in... either the battery was being discharged or the damn thing would go off at about 50-60 mph and the horn would blow and hazard lights would flash! (sure I looked like I was in a hurry and important LOL!) My buddies would give me so much ****. Or When we would go to take off and it was a cool place to check out a river or whatever then BEEP BEEP cause you forget the thing set. Too funny. Alarms---(coneheads) Ahh memories I will cherish them

Electric Head · 10-20-2009, 06:51 AM

I hooked up the new battery tonight 12.8V, both fobs still work, manual code is still the same, re-initialised the TMAT, now tomorrow morning I'll give it a start, check the running voltage to see if the charging system is trying, if all is good, off to work to empty the tank by Saturday just so I can pull the battery back out to rip the wheels off for new tyres and give the calipers a clean, some new brake pads, brake fluid, speed bleeders, and fork oil.

Electric Head · 10-21-2009, 12:17 AM

Battery measured 12.8V before starting this morning, 14.2V while idling. I was looking in the owner's manual and 11.5V has ZERO charge, so my less-than-6V battery must have been kaput.