Not to disagree with anyone but to draw a battery dead in a matter of minutes would take the kind of amperage that the starter would draw, you could find a problem that big with your nose by smelling for burning electronics or wires. Usually a battery with a single bad cell will display the characteristics that you have described.
riverattcom, I do a lot of auto electrical work and have never seen a short that would draw a battery dead in minutes. The entire system is protected against that kind of a short with both ATC and Maxi fuses. Now if you have a draw that runs the battery down in say 48 hours and the battery goes dead as many as three or four times the odds are you will have a cooked battery. Anytime you think you have a short it should blow a fuse, if you have a draw it is easy to check and track with even a simple dvm. It really is one of the easiest parts of an automotive system.
I should explain, yes I am an ase certified master in auto electronics. A short is a direct connection of power to a ground, this causes burning and sparks in most cases and every system has fail safe devices that open. Fuses, thermal limiters, fuse able links, etc. To drain a battery in minutes with a short would generate about as much heat as an arc welder would. and would require at least 2 gage wire to sustain the load without melting.
Now a draw is when you have a component that does not power down such as a relay or field as the result of poor wiring or improper wiring. This will usually result in an amp draw of around 1-2 amps and this will usually knock a battery dead in around 48 hours. This is not a short and this can be checked and isolated with a dvm by first determining the amount of draw and then isolate circuits until you can identify the source of the draw.
Now if you continue to replace battery's without repairing the draw the new battery will have a very short life as these are not deep cycle batteries and are not designed to be fully discharged without doing cell damage. Most batteries will not survive more then four full discharges before they no longer have any reserve life, this would explain anything being on for a couple of minutes causing a no start. IMHO
I think the battery is bad but I would guess the life of the batteries is being cut short by improper wiring. Just wanted to clarify what I call a short versus a draw.
Riverrattcom the HD factory battery is an AGM (Absorption Glass Mat) , it is a completely sealed battery and should be very durable against anything like a dry cell. But a regulator malfuntion would be easy to determine with a dvm again. This is a case were some checking will need to be done. I also suggest test the battery with something like a good VAT 40 to be sure exactly what it is doing and is capable of doing.
owenwil I don't see a fight here at all, I think that we are looking at the original problem from different view points but in no way could either of us say more as this is a problem that really requires a hands on the bike to determine and everthing else is speculation.
greenham with solid state circuits that we have these day's I do not suggest the bulb test. A dvm using the amp load reading is the only way to test for a draw. Most meters will not allow over 10amps so be careful and do not key up on the meter. If you want to test higher loads you will need a current shunt to hook up on the meter.
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