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Voltage issue 06 GPX

Discussion in 'Technical and Troubleshooting Torque' at netrider.net.au started by [swifty], Nov 15, 2010.

  1. Hi All,
    So I noticed the other day my tail lights are not working, nor are my behind speedo / tacho lights... I checked all of the fuses in the fuse box, and couldn't find any broken. I put a multi meter on the tail light and tested the brakes etc. and there appears to be voltage going through - but it seems too low... anyway, have replaced the globe - but still no love... could anyone throw me a bone before I send her off to the mechanics?

  2. At a guess, and I may be wrong, :) your have two separate issues. Firstly I assume the bike starts and runs OK indicating good charged battery?

    I would say instrument lights are blown globes see if you can remove them and check.

    Fuses can look intact but not be. Check you have 12V to frame on both sides of the fuse.

    Just to clarify: You have no brake or tail lights or you have one and not the other?
    This is more than likely poor earth return to the frame but if you are keen to have a go with your multimeter check voltage from globe positive to battery negative or bike frame rather than across the globe, Is that normal 12V or so. These tests are with globes in by the way, some faults will not show unless you are drawing current.

    Good Luck. :)
  3. As Chris says check with a load (lamp) in. High resistance joints show as OK with no load but the light don't work.
    IF you get 12V without the lamp in, and the lamp tests OK then you need to chase a loose or poor joint.
  4. hrmm, thanks Ducfreak... if I'm reading the multimeter right - its only very low - less than 1v without a lamp in. What controls the voltage?

    is there potential for a regulator or similar to be faulty?
  5. Sounds like a connector undone (or partially), As OP says check to bettery neg as well, If OK to battery neg (12V) you have a bad earth connection, if still 1v then bad +ve connection , fuse, connector , wire?

    All the lights etc run on 12V

    The only regulator on bikes is usually just the charging one, for looking after what comes out the alternator.
  6. i feel like a bit of a dumbass...
    had the bike half apart, couldn't for the life of me figure it out... i thought for shits and giggles i'd test all the fuses (this is after having them all out mind you)

    and found that the fuse was broken... what a fool. for the life of me i still cant see the break in the fuse tho.

    ah well... lesson learnt, bike is fixed :)