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Latest post Fri, Apr 6 2018 10:30 AM by sfranta. 12 replies.
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  • Wed, Apr 4 2018 8:50 AM

    • stubborne
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    • Mt Pleasant, SC
    • Posts 48

    No power - Ground issue

    Hi folks.. 1995 FXSTC.   New battery and plugs a couple months ago.   Took off in morning, no issues, stopped for lunch.  Turned ignition on, no power at all.   Turned ignition switch off and back on real quick, bike fired right up.   Later in the afternoon, not so lucky.   Turned switch on, no power and could not get power by working the switch a few times.

    Multimeter shows good voltage at the battery terminals and + to bike frame.   Turn ignition switch on, voltage drops to about .25 across the terminals and to bike frame.   Same if I measure on the power terminal on the ignition switch.  

    Looking for advice on where to start troubleshooting this.   Sound like a bad ignition switch or could this grounding issue be somewhere else in the line.   What other spots should I measure voltage to isolate, or any other tests you would recommend to isolate??    

    Much appreciated!

     

     

     

  • Wed, Apr 4 2018 10:04 AM In reply to

    Re: No power - Ground issue

     does the power come back on for a brief second, then nothing? if so, it's probably a bad ground. i had this happen on mine, the ground on the back of the primary cover came loose, and blew the main breaker. other possible causes, bad run/off switch on the handlebar, or a bad ignition switch. if the switch is still original, it probably has exposed rotary posts under the switch which can become corroded, and sometimes a piece of emery cloth can cure that one. a bad circuit breaker, while rare, could also cause this, as well as a bad connection in the power wires. let us know what you find

     

  • Wed, Apr 4 2018 10:05 AM In reply to

    • stubborne
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    • Joined on Tue, Jan 27 2004
    • Mt Pleasant, SC
    • Posts 48

    Re: No power - Ground issue

    bit more info..  Fuses check ok, continuity and ohm test. 

     

  • Wed, Apr 4 2018 10:07 AM In reply to

    • stubborne
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    • Mt Pleasant, SC
    • Posts 48

    Re: No power - Ground issue

    no power at all, completely dead.  What's a good test for the ignition switch?   I had my multimeter set to continuity and when the switch is on, I get a beep on all terminals.   When off, beeps only on the hot terminals.  I'm in the process of pulling every wire, sanding and applying some dialetic grease around the ignition and fuses.

     

  • Wed, Apr 4 2018 10:13 AM In reply to

    • Ironhead
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    Re: No power - Ground issue

    stubborne - first thing I would do is use the ohn meter across the switch - make sure it isn't dirty / worn out inside.  It may take several tries to verify the switch is "going south" .

    If it isn't the swicth, then check that the positive and negative cables don't have a break in them - this isn't uncommon on a 20 year old bike.

    Hook your ohm meter to each end of the wire and "jiggle" the wire and check for resistance changes.  If not those two wires, use your ohn meter to follow from the battery to through the fuses to the switch to the ignition, . . .

    BTW, when you turn the switch on and there is no ignition, do the headlights work?

     

    The first tool out of the box should be the "book"  Geeked

  • Wed, Apr 4 2018 10:19 AM In reply to

    • FX
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    Re: No power - Ground issue

    Stubborne. The continuity test on the switch is inconclusive. you would have to put a load on it to test properly. I would lean toward the switch being bad, and not handling the amps. Take the switch out, and see if the system works by jumping the wires,(bypassing the switch). you can do the same with the handlebar on/off switch...Your service manual will show you which are the ignition wires to jump...

    FX

    Don't force it, get a bigger hammer.

  • Wed, Apr 4 2018 10:42 AM In reply to

    • stubborne
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    • Joined on Tue, Jan 27 2004
    • Mt Pleasant, SC
    • Posts 48

    Re: No power - Ground issue

    No headlights or dash lights at all.   I'll keep testing with the ohm meter.

     

  • Wed, Apr 4 2018 10:53 AM In reply to

    Re: No power - Ground issue

     if there is no power anywhere, then the problem would have to be in the main ground, or the ignition switch, the power wire to the switch, the main breaker, or the wire and connection between the main and the battery. if the problem was downstream from the ignition switch, you wouldn't have a loss of power to everything, just the individual circuit. in other words, if the grounds are ok, the problem has to be between the battery positive and the ignition switch

     

  • Wed, Apr 4 2018 10:54 AM In reply to

    Re: No power - Ground issue

     what is battery voltage? does it change when you wiggle the posts?

     

  • Wed, Apr 4 2018 11:03 AM In reply to

    • stubborne
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    • Joined on Tue, Jan 27 2004
    • Mt Pleasant, SC
    • Posts 48

    Re: No power - Ground issue

    Had the battery on the tender last night, good strong 12.75V.   When I hit the ignition switch I read .25 volts on the battery terminals and from positive to bike frame.   Same goes for the ignition switch leads.   Although I read only around 11V at the hot lead on the switch when it is in the off position.   When the switch is ON, I read .25 volts everywhere. 

     

  • Wed, Apr 4 2018 11:38 AM In reply to

    • FX
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    Re: No power - Ground issue

    The switch is not handling a load, or system ground to frame/engine is weak...Try running a jumper wire from bat neg. to engine, and frame, to check for bad ground.

    FX

    Don't force it, get a bigger hammer.

  • Wed, Apr 4 2018 2:28 PM In reply to

    • stubborne
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    • Joined on Tue, Jan 27 2004
    • Mt Pleasant, SC
    • Posts 48

    Re: No power - Ground issue

    Thanks all for your support.... The bike is stuck at work parking lot, so I'm towing it home tomorrow morning.   I'll be able to pull the tanks there to get better access.   More to come... 

     

  • Fri, Apr 6 2018 10:30 AM In reply to

    Re: No power - Ground issue

     i was re-reading this post, in the original, you say you checked fuses. this bike should not have fuses, it should have a main 30 amp circuit breaker between the battery and the ignition switch, and 3 15 amp breakers, one for ignition, one for lights, one for accessories, downstream from the ignition switch. if it has fuses, i'd say someone has done some modifications, which would probably complicate the trouble shooting process

     

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