06-16-2008, 11:03 AM | #11 | |
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Hard to give a good answer to the second part. Resistance readings CAN be decieving......because of the aforementioned secondary or back-door grounds.
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06-16-2008, 02:15 PM | #12 |
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Change the name of your bike to Christine, LOL
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06-16-2008, 03:55 PM | #13 |
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Man, at this point, I would LOVE it if this thing was like Christine--at least Christine fixed herself when she was broken! :-) I don't mind if she runs over a few people and catches on fire, as long as she'll self-repair...
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06-17-2008, 12:06 AM | #14 | |||||||
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Also 2) I would replace the "twisted together five years ago" wires with a solder connection, or if you don't like soldering, try to make a 'fresh' twist (cut old wire ends off, strip a little plastic, and twist together again, with a wire cap. Or, maybe better: 3) try to replace the twisted connection with a diode (normal silicon diode, Radio Shack you know, they're not expensive. To make it fail safe get 2 diodes and put them in parallel, but with opposing direction. Then, it doesn't matter which way you connect them, and you will always have 0.6 V over them. The signal lights may just start blinking normally (this is a wild guess....). Quote:
Apart from checking the entire ground circuit thoroughly, as Easy suggested, I would not know where else to look... We're running out of parts to consider... Voltage does not say much. It shows that there is a connection, but not how good it is. Resistance measurements are a little better, so undo the positive battery wire and get the ohmmeter out. Measure between negative battery pole and every possible ground connector. As I said before, when testing the 'ground' wire that goes via the [side stand switch or the] 'override plug', put the bike in gear. When you measure, do 'wiggle' the wires a bit to see if the reading fluctuates.
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06-17-2008, 02:10 AM | #15 |
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Will do--I have a soldiering iron, so I will give that a go just to be sure. I actually did re-twist the override plug wires, but it might lower the resistance a bit is I go ahead and soldier it.
To double check, to test the diode, I need to set my DMM on Volts, and put a lead on each end of the diode circuit, and then switch the leads, correct? One way should give me a reading and the other way should not (or at least a much lower reading), correct? So to re-state your instruction for clarity, I take the pos. battery cable off, and put the negative DMM lead on the negative battery post (or on the frame for that matter since the neg. battery terminal just grounds to the frame anyway...), and the pos. DMM lead to every ground wire I can find in the system starting with the grounds closest to the battery. The first place where I get either an OL reading or 0.0ohm resistance back to the battery will give me the segment that has the problem. And resistance should increase the further I get from the other lead, I think. One thing I am not is and Electrical Engineer, so does this sound right? 5th Bike, and Easy Rider, thanks for all the time you guys have spent typing and thinking about this. I really do appreciate it. Login or Register to Remove Ads |
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06-17-2008, 10:02 AM | #16 |
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No, your DMM should have a special 'diode check' mode, with mine it is a 'sub'mode of the ohms measurement, a little diode symbol appears in the display, and its readout is in volts.
When you measure resistance, anything close to 0 ohms is good. As far as I know, the requirement for a house's ground wiring is that the resistance to ground should be less than 2.5 ohms. OL means that there is no connection, and indicates a problem. Do make sure you make good contact, little layers of oxidation on metal often make it seem that you have no connection. Carefully poke the sharp point of the DMM lead into the metal, then you should be OK. (Edit: about 4 spelling errors, and: to at least try to avoid the 'false ground' problem that Easy mentions below, try to unplug as many connectors as possible, and connect only those needed to complete the path to the negative battery pole. Do start with the green wire from the side stand relay pin C (unplug first)) Good luck.
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06-17-2008, 10:36 AM | #17 | |
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If you are going to try to trace grounds with the ohm-meter, put one lead on the (-) battery post or the cable that connects there. DO NOT connect it to the frame. We are, after all, maybe looking for something that is connected to the frame but NOT to the negative battery. And I've got to mention again (appologies to 5th) that trying to trace the grounds with a ohm-meter may not be the best way......because of secondary, back-door grounds. If you DO that, be suspicious of any reading above 0 ohms. Calibrate the meter by shorting the leads together to be sure a dead short actualy reads 0. As long as we are doing this, maybe I should define: secondary, back-door ground. :roll: It is a path to ground through another branch of a circuit or through another device when the physical ground is absent. If, for instance, there are several things in close physical proximity that all need a ground, it is common to tie them all together and the run a heavier wire to the frame ground. If that common wire goes open, the negative side of the devices are still tied together. Sometimes one, or more, of those devices actually supplies a partial path to ground........so that a tiny bit of current still flows.....and an ohm-meter will still give a reading........although not enough current to make things work right and the meter will not read a "good" zero. Whew. Sure hope "we" get this fixed soon. All this worry and effort is tiring me out !!!! :lol:
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06-18-2008, 01:58 AM | #18 | |
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This weekend I am gogin to take the bike completely apart so I can get to everything, and spend the day in hell trying out all your good suggestions. How about if I get my web cam, and a long USB cable, and we can get on Skype and you guys can take turns telling me what the hell to do, and making fun as look like a monkey having sexual relations with a football and sounding like an adult version of Yosemite Sam. Sounds like a good Saturday, right? To clarify one last thing, the longer a wire, the more resistance it has, and the higher Ohms, right? So it seems to me that if you have an Open Line (OL) early in the system, then it will either read OL or it will show a very low resistance. Another way to say it is if I am measuring ohms in a 10' wire, and I get no resistance, then something is likely WRONG, correct? Who'd of thunk that you'd be given DMM lessons on the GZ250 page. We have now elevated this forum to a WHOLE other dimension...do I get a free status upgrade from "Newbie" to "Official Pain in the Ass"? |
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06-18-2008, 07:33 AM | #19 |
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Copper wire has very low resistance. For example, ten feet of 18 gauge wire would have a resistance of 0.0751 ohms. If you have a wire on your bike that has any significant resistance. Depending on the meter you have it might not be able to accurately read resistance this low.
Wire Gauge Resistance per foot 4 .000292 6 .000465 8 .000739 10 .00118 12 .00187 14 .00297 16 .00473 18 .00751 20 .0119 22 .0190 24 .0302 26 .0480 28 .0764 |
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06-18-2008, 10:36 AM | #20 | ||
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So, when measuring something that should be connected together with a wire (or equivalent), you should expect to see 0.0 ohms (or maybe 0.1). Anything higher than that and there may be a problem. (The first "problem" being that the meter leads are not making good connection!) I'm not really fond of digital meters. I still like to see that needle move.
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