Please help diagnose an electrical problem. Is this a short? | GTAMotorcycle.com

Please help diagnose an electrical problem. Is this a short?

johnp

johnp

Well-known member
Today, month old battery would barely turn the bike over; didn't start. Been sitting a week, maybe two.

I am sad with electrical stuff. From googling got this

http://www.motorcycleanchor.com/motorcycle/how_to/mc_electrical.html

Which says to test for a short

[1] disconnect the negative. Keep the positive connected, and
[2] take voltage [EDIT should be AMP reading not volts] from the lead to the battery terminal, and
[2] if it's non-zero (how about 10 volts?) then you have a short,

According to this test I have a short.

I pulled out all the fuses and still had 10 volts showing, so still a short? I've got two likely suspects:

- the alarm system that I installed, when first bought (works fine), and
- the horn which works off and on, depending on ???.

For a 2007 Kawi ZZR600 with low mileage.

Any suggestions? Is that how you check for shorts?
Thanks in advance.
 
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Most alarm systems have a residual draw. I would disconnect the alarm and proceed from there
 
johnp said:
Been sitting a week, maybe two.
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RockerGuy said:
Most alarm systems have a residual draw. I would disconnect the alarm and proceed from there
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^^ this. Any bike that sits for 2 weeks not on a battery tender, with an alarm, will most likely be almost dead.

-Jamie M.
 
It will not be a short circuit (that would blow a fuse), it will be something in the bike that draws a small amount of current with the ignition switch off.

For the original bike, the only thing not switched with the ignition is the digital clock on the instrument cluster, and that draws so little that it won't be an issue.

Alarm system is a prime suspect.
 
What the OP described is a parasitic draw test. Generally anything under battery voltage indicates that there isn't a significant draw. That doesn't mean that showing 10 volts is good that could be battery voltage given the condition of your battery.

A motorcycle battery, especially if older, won't support the draw of an alarm or other drains over a period of two weeks.
 
toysareforboys said:
Have you used the new Lithium batteries at all? How do you think a Shorai battery would last running a constant draw line an alarm? http://www.shoraipower.com/p-414-lfx14a4-bs12.aspx (the one that goes in my R1)

-Jamie M.
Click to expand...

I have used lithium in my race bike and have a Shorai in my DRZ ... they're outstanding batteries. You can't trickle charge them like a lead acid though, once they're charged they pretty much stay that way (for a very ling time)
 
toysareforboys said:
Have you used the new Lithium batteries at all? How do you think a Shorai battery would last running a constant draw line an alarm? http://www.shoraipower.com/p-414-lfx14a4-bs12.aspx (the one that goes in my R1)

-Jamie M.
Click to expand...

The problem with lithium batteries is that they MUST NOT EVER BE DISCHARGED below a certain voltage that represents something like 20% charged. If this happens, even ONCE, the battery can never be recharged - essentially, it is "bricked". If you have a significant current leak with the ignition off (e.g. an alarm system), this can very easily happen without you knowing about it.

The digital clock etc that is original equipment on your bike represents an extremely tiny current drain which isn't going to be an issue unless you leave the bike sit for a few years without ever starting it or touching the battery, but alarm systems have a much greater current drain.
 
Brian P said:
The problem with lithium batteries is that they MUST NOT EVER BE DISCHARGED below a certain voltage that represents something like 20% charged. If this happens, even ONCE, the battery can never be recharged - essentially, it is "bricked". If you have a significant current leak with the ignition off (e.g. an alarm system), this can very easily happen without you knowing about it.

The digital clock etc that is original equipment on your bike represents an extremely tiny current drain which isn't going to be an issue unless you leave the bike sit for a few years without ever starting it or touching the battery, but alarm systems have a much greater current drain.
Click to expand...

Isn't there a chip on those to prevent them from being discharged totally?
 
Brian P said:
The problem with lithium batteries is that they MUST NOT EVER BE DISCHARGED below a certain voltage that represents something like 20% charged. If this happens, even ONCE, the battery can never be recharged - essentially, it is "bricked". If you have a significant current leak with the ignition off (e.g. an alarm system), this can very easily happen without you knowing about it.

The digital clock etc that is original equipment on your bike represents an extremely tiny current drain which isn't going to be an issue unless you leave the bike sit for a few years without ever starting it or touching the battery, but alarm systems have a much greater current drain.
Click to expand...

Ah.

Looks like the special charger is pretty much a must have when you get that battery: http://www.shoraipower.com/p-184-sho-bms01.aspx
 
RockerGuy said:
Isn't there a chip on those to prevent them from being discharged totally?
Click to expand...

Nope. Switch the ignition off without using the key and walk away? Bye-bye, battery. Bricked. Junk. They won't warranty this type of situation, either, and they explicitly warn against it in the instructions. This is the bad thing about lithium batteries. I always use the key to switch off, so this situation is not a concern to me, but I've seen lots of people use the kill switch rather than the key, or accidentally switch the key to the "park" position leaving the running lights on. BAD NEWS.

Long before I knew about this, I bricked the battery in a cordless drill while doing the drywall in my basement. Same issue.

Laptops, cellphones, etc have their own protection against completely discharging the battery, but motorcycles don't, and there is no isolation contactor or any other such thing built into the battery. Given the need for any such hypothetical device to handle the full current of the starting motor, this would have to be a serious, heavy-duty contactor, not just a little "chip" ... and a contactor requires constant voltage/current to pull in; not a good plan ...

silverbullet132 said:
Ah.

Looks like the special charger is pretty much a must have when you get that battery: http://www.shoraipower.com/p-184-sho-bms01.aspx
Click to expand...

I've found that as long as the charging system in your bike puts out at least 14.4 volts, the battery seems to survive.

Old style charging system designed for flooded lead acid (the type where you have to maintain the water level) often don't have a sufficiently high charging voltage. Can't use a lithium battery in an old FZR ... at least, not for long ...
 
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If you run the test described by the OP, shouldn't you be measuring CURRENT not voltage? Since you're connecting the multimeter in series with the battery, I think you should be measuring milliamperes right? I had to do the same thing since I had a brand new battery die when the bike sat for a week (no alarm system installed) and I was worried something was draining the battery. The first mechanic I went to measured voltage, but the service guy at Cycleworld said it should be current.

Al
 
HA10 said:
If you run the test described by the OP, shouldn't you be measuring CURRENT not voltage? Since you're connecting the multimeter in series with the battery, I think you should be measuring milliamperes right? I had to do the same thing since I had a brand new battery die when the bike sat for a week (no alarm system installed) and I was worried something was draining the battery. The first mechanic I went to measured voltage, but the service guy at Cycleworld said it should be current.

Al
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Both work. Using a voltmeter to measure parasitic loss is from the days of analog voltmeters and when most shops didn't have easy to use ammeters that measured such low draw. The voltmeter method works very well and you can tell by the needle deflection what type of draw is being measured.
 
OOkay, lets clarify some things

Running the volt meter in series with the battery terminal, ie, disconnect one lead, attach one side of voltmeter to battery the other side to the now disconnected lead while the voltmeter is on the AMP setting will tell you your parasitic amperage draw. Measured in amps or miliamps....there will always be some. example, if your battery is a 7a/h and you are reading a 1 amp draw it will take 7 hours to hypothetically discharge the battery. More like 3.5 as lead acid batteries dont like being discharged more than 50%. Most likely you wont have such a heavy draw, it will be much lower.

Once you've discovered the parasitic draw its time to isolate it. Start pulling fuses until the draw disappears or drops drastically. At that point find out whats on that circuit and go from there. It may not be an alarm...it may be a frayed wire thats only touching the frame by a few strands...not enough current will be pulled to pop the fuse but enough that those few strands act as a light bulb element.

Another thing. The battery that are the new fandangled Lithium batteries are NOT LIPO....They are NOTHING like the batteries in your cellphone, laptop, power drill etc. These batteries are LiFeP04. Totally different chemically and electrically. A lipo battery is considered fully charged at 4.2V per cell and considered discharged at 3.5V nominally. They can go down as low as 3V but they wont like it and their lifespan will be shortened considerably. Now the LifePo4 battery cells are considered fully charged at 3.6V. Place 4 in series and you have 14.4V, incidentally that is the voltage that most 12V DC circuits charge at. Another beautiful part about these babies is that they can be discharged to zero and not care...They wont like it but their lifespan will be measured in hundreds of discharges to zero vs thousands normally whereas the Lipos will go from hundreds of discharges to dozens. The other great part is that the cells are self leveling. Each individual LifePO4 cell will balance its voltage with the rest of the cells in series. LIPO's cant do that...thats why you have to manually balance them using a Lipo charger. Internal resistance variations means that individual cells are charged and discharged differently and after a few dozen discharges the 4 cells in a series may read full which is 4.2x4 = 16.8 but one may be 3.7V, 3.8V, 4V and last one will be 5.5V. As you can see, one is critically dangerously over charged and will blow up!
The other reason Lipo's are not used is that as you can probably tell Voltages dont work. Lipos are full at 4.2V, no combination of cells in series will give you a max of 14.4V and a minimum of 12.5V.

So how is it that LifePO4s can be smaller, lighter but be used to start a motor? Discharge rate measured in C. So a battery with a 1C rating will discharge itself at its A/H rating and give you the promised amperage. Example. The 7a/h lead acid battery will give you 7amps at 1C. Discharge it harder at 4 or 5C and the internal resistance will drop its output amperage significantly, so you will ask for 30amps but it will discharge MUCH faster than time it should discharge at.

The LifePO4's cells can discharge anywhere from 20 to 50C without suffering large internal losses. So that 3amp hour cell can provide 40 to 50 amps without killing itself.

class dismissed.
 
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My actual field experience with a Shorai battery on a charging system that operates at 13.5 volts on a good day (designed for old style flooded lead acid, the type where you have to check and fill the water level) is that it dies in two track days, won't crank the engine on the third, and will not accept a charge thereafter. There is a serious warning in the instructions not to allow the battery to discharge to below 12.8 volts (at rest, not charging) and that they won't warranty a battery that has been discharged below this. Not sure I buy the claim that you can discharge a LiFePo battery (or whatever a Shorai is) to zero and recover ... actual field experience is that you'll "brick" it.
 
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