Electrical Short?

[Bluechrome]

Hi

Your help would be much appreciated.

I noticed that when I reconnected the Earth lead to the Battery terminal (-) there was a spark between the terminal and the lead - when everything was switched off. The Positive lead was connected to the positive terminal at the time.

Is this normal? I expected a spark only if the ignition was turned on at the time of connecting?

 

I disconnected the earth lead and measured the Volts between the negative battery terminal and the earth lead and it is the same as between the two terminals (+12V). Do I have a short and if so how do I go about finding it?

My electric experience is very limited so I hope you will bear with me.

Thanks in advance.

[cowpuc]

Not sure,, I know your scoot probably has a clock,, not sure if there is enough of an amp draw on the battery that you will see a spark - I highly doubt it so I am voting nope, shouldnt be sparkling,, if it were mine I would probably begin the process with pulling fuses, all of them.. Then check it again and see if its still there.. If it is I would then remove the left side cover and unplug the 3 wire stator terminal (has three white wires - should be attached right along the downward frame) and try it again.. If the fuses nock it out you can either test each circuit with an ohm meter and find the bad circuit or you can replace the fuses one at a time as you watch that battery..

Once you find the bad circuit its just a matter of chasing down the device (every thing from a light bulb to a starter is a device) or wire that has gone to ground.. Process of elimination I reckon...

Cant wait to read what the pro's have to say about all this:big-grin-emoticon:

[utadventure]

When you connect the negative lead (and the positive lead is already attached), you are completing the circuit and any device that uses power without the ignition switch on (radio, clock etc) will start to draw power and can cause a minor spark to jump once the lead is close enough to complete the connection.

 

Should be nothing to be concerned about unless your battery is draining out.

[winston66]

If your volt meter has an amperage function, the first thing that I would try is to actually measure what current drain there is when the ignition switch is in the off position. Place the meter leads in series between the negative lead and the negative post of the battery. There should be a negligible amount of current draw shown, ie only what the clock would need to operate. then turn on the accessory function, the amperage reading would show how much current is being used if any of your accessories are switched on , then turn the ignition switch to the on position and see what the meter says, this will show you how much current draw the bike uses prior to starting, Ie lights and ECU draw etc. make sure that the meter is set to the ten ampere position for this test.

Do not attempt to start the bike with the meter in series with the negative lead and the battery as you will either damage the meter or blow its fuse .

Take a note of the various readings and the switch positions (either on or off) for the various accessories that you may switch in or out of circuit and let us know of the results.

Regards ,

Winston66,

Northampton , Western Australia

[frankd]

You may be charging a capacitor and nothing is wrong. Connect the lead and leave it for a few seconds. Then disconnect it briefly and reconnect it. You probably won't see a spark the second time. If your battery isn't going dead, don't worry about it.

[Flyinfool]

IF you had a short then that spark would / should have already blown the fuse on the shorted circuit.

 

I agree with Frank that most likely you were charging some capacitors with that first contact.

 

If you do suspect a short and do not want to risk your meter, get a small 12V light bulb like the type used in the dash (type 194) attach wires to the bulb, connect one wire to the negative battery cable, and the other wire to the negative battery terminal. If the bulb lights up bright you have a problem that needs to be found. If the bulb lights up dim no mater how slightly, then you have something drawing power that will be enough to drain the battery. A dim bulb you can then safely use your amp meter to track down. A bright bulb could be a direct short that you need to find before putting your amp meter inline. Best way to find t is to have the bulb in and lit, and start pulling fuses till the bulb goes out, now you at least know which circuit has the problem.

 

Hopefully you do not have a case of someone having wired up something with no fuse and the problem in the unfused circuit.

[Bluechrome]

You guys are great!

I used a test light between the battery terminal and the lead.It glowed dimly for a few seconds then stopped. Within a few seconds I used the light again and no glow.

A half an hour later it glowed for a few seconds and then stopped.

I am much relieved. It seems it is just charging a capacitor and nothing wrong.

Thanks for the help and my peace of mind.