Sportster battery keeps dying (what's up)

[Silver]

My 2009 XL1200C has been perfect since I got it. Now for the first time I rode it 3 days in a row to work in straight rain.

The 4th day I went out to ride to work (no rain), I went out to start the bike and dead battery (not even any lights or anything). Put on a trickle charge overnight and bike starts up and ride around for an hour. Bike will start up right away after bike is shut off so I'm thinking it's kept it's charge.

Next morning dead again. Any suggestions. I have an HD security system on it and instead of the usual pulsating key light, it's on a steady bright red after I turn off the bike. I also notice I now don't always get that sound of the Fuel Injector before start up. Weird...

I'm thinking something is running after I turn off the bike but can't put my finger on it. Did the ride in the rain cause this?

Please help.

Thanks,

Silver

PS - I didn't take out the key on ACC it was completely off.

[snowman]

Check the cable ground connections...

[joesporty]

and all the fuses...

[Screw Loose Dan]

Check the all the battery connections and fuses (as the others mentioned). Also, pull the relays and see if there is any corrosion. It's a well known issue with the EFI bikes that they goofed with the wiring harness and the relays often get corroded. There's a few different symptoms, one of them being battery dying because the corrosion allows the battery to drain.

Do you have a voltmeter (and know how to take volt readings)? It's pretty easy to check if the charging system is working.

[PaulDM]

I had the same symptoms, dead battery after sitting overnight. In diagnosing the electrical drain I noticed that the efi pump was slowly running. I replaced the relay and it's been fine since. Last week the bike didn't want to start, it felt like a problem with the switch itself, I broke out my spare relay and installed it and that problem went away too.

[Bone]

Yup to what Dan said - I seem to remember some threads about corroded relays allowing the IAC valve to constantly cycle with the key off which would slowly drain the battery.

[LuxBlue]

+ 1 on everything said here. Your riding in the rain and / or washing has corroded your relay terminals resulting in your fuel pump probably running all the time. Easy fix to clean the corrosion and I would recommend spraying the back side of the board with a conformal coating of some sort.

[Bone]

FWIW Lux, I've never heard of/seen the fuel pump run because of the relays...because I'm pretty sure it takes the ECM to complete that circuit, but it's same idea, some components of the EFI system are cycling when the relay clicks shut... I guess in theory the fuel pump might cycle too then I dunno

[LuxBlue]

Originally Posted by Bone

FWIW Lux, I've never heard of/seen the fuel pump run because of the relays...because I'm pretty sure it takes the ECM to complete that circuit, but it's same idea, some components of the EFI system are cycling when the relay clicks shut... I guess in theory the fuel pump might cycle too then I dunno

Could be? What I should have said is corrosion is causing some kind of sneak path on the relay board making some component run and drain the battery.

[crospo]

Pull the main 30Amp fuse overnight.If battery is still fully charged at least you know there's a drain somewhere.Then you can likely rule out the battery and charging system.