Voltage Drain

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OK, this is a question for a friend. Its not about a Vmax. Its about a ...gulp......sportster. He has an '05 883c. We put a 1250 big bore kit on it this winter. Runs fine. His trouble is that he has just put the 3rd battery in the bike. Its only 4 years old! I told him to try out Lankee's trouble shooting idea for a battery drain. Take the positive wire of the battery and put your meter in between + post of battery and the wire. Well, when he did he was reading 12.4 volts. This was over the phone to me. I said, turn your key off! LOL. Sad part, it was off. When he turned it on the reading really didn't change. I think he said it dropped a bit actually. He mentioned to me that the battery has 2 wires on the positive terminal. One goes to the main bike fuse and one to a wire harness somewhere. The one that goes directly to the main fuse is what is showing the 12.4 volts.:ummm:

My question is, is there any logical reason why it would be using this voltage with the key off? He has an alarm system but it was turned off. No aftermarket electrics other than a tach and some led lights for show but they are on their own fuse. I may go over his place tomorrow and see if I can help find something. If I do, I plan to start pulling fuses to see if we can isolate the circuit its coming from. Other than that does anyone has any suggestions or insight that may save some time?:ummm:

Oh, and by the way, I did try Lankee's test on my max cause I've never heard of it before. I used a test light cause my meter was in my work vehicle. It does in fact work. Key off, no light. Key on, bright red bulb on the test light is on.unk: We tried the test on my boss's '03 sportster and it came up .1 Volts key off, 12.1 Volts key on (battery sitting in a cold warehouse all winter and the bike fired right up 2 days ago):clapping:

 

[95spfldmax]

You got the right idea about pulling fuses to isolate the problem. Include the alarm fuse and any others as well. Plug back in one-by-one.
Be sure to post what you find out here. I'm/We're always interested in what these electrical problems turn out to be.:ummm:

 

[maleko89]

+1, you're on the right track.

Having two red wires from positive battery terminal is normal. The Vmax has the same deal. One goes to the main fuse and on to the key switch while the other is for the starter relay/starter.

 

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Did a little digging on a sportster specific forum and found a little useful info. The people there were not very helpful however. Anyways, he went to do a test to see how many mA he was pulling and blew the fuse in his meter. Tried another meter and the same thing. From the research I found something saying the check the fuse block for corrosion. It is a common issue with '04 and up sportys. He called me back and said the whole thing was covered in corrosion. He cleaned it all up and put anti-ox on everything. Went out and got some new fuses for the meters. Did the mA draw test again and no more blown fuses. It was pulling about 3.1 mA. The spec that I found for his bike was 3.0 mA so I guess that's close enough.

By the way i tested the max in the same fashion for a mA draw with the key off and it wouldn't register. Had to adjust the range to microAmps (uA). My draw was 0.3 uA. I figure thats pretty good. Key on, the draw was somewhere around 7A if I remember right.