I think there's an electrical ground somewhere on my sportster custom. Sometimes overnight the battery is totally dead, some times its weak enough no able to crank the motor. Sometimes its ok after a couple of days. What I do at the moment is everytime I leave the bike overnight I just unplug the wire going to the ECM. Then theres no problem with the battery draining out. Whats the easiest way to find the ground? Just remove the tank & check all the connections?
I think the problem started when I washed it with power spray. I didnt notice it at first then it happened a few times. I thought it was a defective replacement battery. But now I know theres some kind of ground somewhere. Any suggesttions? Thanks.

 

well i'm not an electrical guru and i'll never pretend to be so hopefully someone will chime in here. however, pick better means of washing your bike. you should never use a power washer dude, never. i have an 08 that i bought in 08 and i have never washed the bike with water yet (except if it rains when i'm out riding). honda spray detailer is all i use and all i will ever use. also, if you're unplugging your ecm at night you really should be pulling that maxi fuse before you do so.

 

What you mean pull the maxi fuse first?

 

Load test the battery yourself first.

Use a meter,,hook It up,,
Voltage should be about 12.5,,don't worry about point this or point that too much.

Now while It's hooked up watch the meter and start the bike.

Voltage should not drop below 10 while the bike starts.
Anything below 10 Is bad,,below 7 or 8,,,your about to be stranded
Follow the ground wire to the motor,,check It.

I wash my 2008 EFI all the time, I blast away with the hose,,even under the seat,,
never had a problem.

 

have you even opened your owners manual?

 

 

Got the bike used. Didnt come with an manual.

 

well i think it would be a wise decision to get one. before disconnesting the ecm, you should always diconnect the maxi fuse first which is the main fuse for the bike located under the batt. cover.

 

This was a problem that drove me crazy on mine too, what it ended up being is a small amount of corrosion that was on the relay box in the fuse panel. Look for two black square relays and pull them out, clean any corrosion that is on the back side where the electrical connectors are. When you plug them back in, put electrical conductive gel to protect against moisture from doing this again.

Hope this helps.

 

Get the HD service book...
It shows where the battery ground goes,,
Get the HD service book...
Get the HD service book...
Get the HD service book...
Trust me