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Main Area => General GS500 Discussion => Topic started by: robo on April 17, 2006, 03:43:36 PM

Title: No Power, Bike Not Starting
Post by: robo on April 17, 2006, 03:43:36 PM
Hey all,

Could anyone give me a hand? Here's what i know so far.

1) No lights/horn/starter when I turn on the ignition
2) Checked fuse, still ok, even tried replacement fuses
3) Checked voltage on battery, still reading ~12.5V to 13V

Last time I went riding, it was dark and late so i wanted to make sure my highbeam was still working. I flipped them on and all of a sudden my bike started sputtering and would not accelerate pass 20km/h or so. The engine revved erratically. I was almost home so i rode it that way. I thought it was just a fuse, but i guess not.

Is there anything else i can check out? Any insight would be much appreciated.

Roel
Title: Re: No Power, Bike Not Starting
Post by: scratch on April 17, 2006, 03:52:42 PM
Wow!

Did you try again with the Hi/low switch in the Low position?

If the Low position doesn't work, I'm conjecturing that with the higher draw of the high beam, that melted a wire and shorted to ground.
Title: Re: No Power, Bike Not Starting
Post by: xtalman on April 17, 2006, 04:47:37 PM
I had a problem with a short that seems similar.  My bike shut off in the middle of traffic and I couldn't figure out why.  I pulled the seat off, started to wiggle the battery, when I heard sparking.  I grabbed the wire harness near the source of the sound and wrapped it several times in electrical tape, and all has been fine ever since.

If you try the same thing, it might be better to try in the dark, where you can see the sparks better.  Not sure if it's really a good idea to be sticking hands in there and wiggling live wires, but it worked for me   :cheers: 
Title: Re: No Power, Bike Not Starting
Post by: TragicImage on April 17, 2006, 05:03:34 PM
what Amperage was your battery reading?
Title: Re: No Power, Bike Not Starting
Post by: robo on April 17, 2006, 05:16:33 PM
Quote from: TragicImage on April 17, 2006, 05:03:34 PM
what Amperage was your battery reading?

I'm not sure how to measure the amperage. I looked it up on the internet and it said to test amperage across a load such as the lights. Am I gonna have to open up my headlight case and test it there? Or can I just test across the battery?
Title: Re: No Power, Bike Not Starting
Post by: TragicImage on April 17, 2006, 05:25:37 PM
a DMM (digital Multi Meter) should be able to test it.
Title: Re: No Power, Bike Not Starting
Post by: John Bates on April 17, 2006, 07:13:19 PM
Quote from: robo on April 17, 2006, 05:16:33 PM
Quote from: TragicImage on April 17, 2006, 05:03:34 PM
what Amperage was your battery reading?

I'm not sure how to measure the amperage. I looked it up on the internet and it said to test amperage across a load such as the lights. Am I gonna have to open up my headlight case and test it there? Or can I just test across the battery?

In a case like this you don't usually worry about amperage. That's for testing the battery capacity.

You're trying to find the source of a voltage problem.  It sounds to me like you have a loose/bad connection that was made worse by the extra current drawn by the high beam.

I would check the main battery connections.  Starting with the (-) terminal.  Remove it.  Then remove the (+) cable.  Clean the connectors.  Check both ends of the cables.  Then place them back, (+) cable first, (-) cable last.


:cheers:
Title: Re: No Power, Bike Not Starting
Post by: 3imo on April 18, 2006, 06:38:37 AM
(http://i47.photobucket.com/albums/f191/eimoytiana/wire.jpg)

no lights / horn / starter
voltage still good.

mmm.  seems easy enough.   don't worry about amperage.  if that were the case your light would still work.

check out the diagram, I bet a wire was worn thin by rubbing against something and gaveout when the highbeam was selected.

good luck.  :thumb:
Title: Re: No Power, Bike Not Starting
Post by: TragicImage on April 18, 2006, 07:42:31 AM
who was the dork that mentioned amperage?


what a jackass....
Title: Re: No Power, Bike Not Starting
Post by: 3imo on April 18, 2006, 07:50:58 AM
Quote from: TragicImage on April 18, 2006, 07:42:31 AM
who was the dork that mentioned amperage?


what a jackass....

it's not nice to call them names.  We like to just keep mentioning the fact that they are wrong. over and over and over......
:laugh:  :cheers:
Title: Re: No Power, Bike Not Starting
Post by: TragicImage on April 18, 2006, 07:55:44 AM
Quote from: 3imo on April 18, 2006, 07:50:58 AM
Quote from: TragicImage on April 18, 2006, 07:42:31 AM
who was the dork that mentioned amperage?


what a jackass....

it's not nice to call them names. We like to just keep mentioning the fact that they are wrong. over and over and over......
:laugh: :cheers:


you people are just SO nice then aren't you?
Title: Re: No Power, Bike Not Starting
Post by: LimaXray on April 18, 2006, 08:34:32 AM
Ok wait a second... there can't be a short otherwise the fuse would have blown.  This is unless there was a short on the red wire going from the battery to the fuse, in which case the battery would have exploded by now or at the very least he would have read 0v across the battery when the wires are connected to it.

My first guess would be a bad ground.  As John said, check the battery terminals.  Make sure they're clean and what not.  Make sure the ground wire that goes to the frame from the battery is ok.  Make sure the point it contacts the frame is clean.  Also check the other ground wire (the black/white one) and make sure its connection/wire harness is ok.

To check, find the rectifier wire harness with the red and black/white wire.  Disconnect it and measure the voltage across the 2 pins on the bike side (not the rectifier side).  It should read the same as it read at the battery.  If it does, try turning on the bike and check it again.  It should still remain close to the same voltage.

I'm going to save you all from the EE speech, but current is very important.  It is just as important as voltage.  12v across the battery tells you next to nothing about the condition of the battery or the electrical system.  Your lights/ignition/start/horn do not run on voltage, they run on power, which is voltage * current.   And another thing, where voltage is measured ACROSS a load, current is measured THROUGH a load. 

When you blow the fuse, you are clearly drawing more then 20 amperes of current which means a lot of things are working the way they should.  In this case, you are not, leaving me to wonder if you are drawing any current.  If you measure a consistent voltage at the rectifier but it still doesn't work, pull out the fuse and replace it with the electrodes of a multimeter so you are basically using your multimeter as a fuse.  Make sure the multimeter's wires go the correct plugs on the multimeter (usually there is one common plug for the black wire, then a 'measure anything' and a 'measure high current' plug for the red wire, make sure it's in the high current one) Select the setting for measuring larger currents.  With the bike off, it should register zero.  Turn the bike on (DON'T CRANK IT) see if there is any current being drawn. 

My guess is it's just a bad battery contact / ground, but if that doesn't fix it, check the current draw and let us know.
Title: Re: No Power, Bike Not Starting
Post by: MarkusN on April 18, 2006, 08:41:06 AM
Quote from: LimaXray on April 18, 2006, 08:34:32 AMTurn the bike on (DON'T CRANK IT) see if there is any current being drawn.
Why not crank it? Since you are in the fuse circuit the starter juice does not go through that branch; no danger of overload of the MM.

Granted, voltage during cranking probably tells more, but I see no harm in giving full load to the system for this test.
Title: Re: No Power, Bike Not Starting
Post by: 3imo on April 18, 2006, 09:00:15 AM
LX - current is important but highly unlikley the problem in this case.

a battery will not up and lose amperage, w/o good reason.  he hit the highbeam switch and all hell broke loose.

I bet his batt is fine.

---

I am trying to print the entire diagram so I can reference it all at once. looking at it bit by bit is pissing me off.
Title: Re: No Power, Bike Not Starting
Post by: LimaXray on April 18, 2006, 09:12:07 AM
Good point I didn't realize there was no protection on the starter...

He can try and hit the starter and see if that gives any differant voltage/current readings, but I doubt it will.  Thinking about it, I would also try jumping the starter manually by removing the starter relay and very carefully jump the starter line to the main 12v line and see if it kicks over.  If that works, then your battery/grounds/battery connections are fine.   

The reason for checking the current draw is to see if there is a large draw somewhere that is not quite a short.  For example, if there was a 1 ohm load somewhere, the fuse would not blow and the voltage across the battery would be ~12v, but nothing would work because this is now the path of least resistance.
Title: Re: No Power, Bike Not Starting
Post by: 3imo on April 18, 2006, 11:01:29 AM
Quote from: LimaXray on April 18, 2006, 09:12:07 AM
The reason for checking the current draw is to see if there is a large draw somewhere that is not quite a short.  For example, if there was a 1 ohm load somewhere, the fuse would not blow and the voltage across the battery would be ~12v, but nothing would work because this is now the path of least resistance.


:thumb: