Electrical Issues

Discussion in 'Electrical' started by Lancer, Nov 28, 2012.

  1. Lancer

    Lancer Junior Member

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    08 Ultra Classic, 47,000 miles, battery replaced last year.

    When driving the headlight and driving lights dim. Voltage drops to 12 volts.
    This lasts about 15-20 seconds, then everything returns to normal. The first time this happened it did throw a code, (low voltage). This happened twice over a two week period.

    I checked and cleaned all battery wires, unplugged connectors at voltage regulator and cleaned them, cleaned voltage regulator ground. The battery ground at the frame was a little tarnished. Figured I had found the issue, I was wrong. Did it again this morning on the way to work, but did not throw a code.

    Ideas? Impending voltage regulator and/or stator failure?

    I found this in self help,

    "To do this with a meter which is more accurate: black lead to battery ground, red lead to each pin on the plug, start with the voltage scale higher than 12vdc and move voltage scale down in steps for each pin. Any voltage is a bad regulator. You may get battery voltage on all three pins on the newer 3 phase regulators. The no voltage is for older type regulators with diode indicating the diode is bad and the regulator needs replacing."

    So how is a 3 phase VR checked? Thanks for any input and ideas you may have.

    Lancer
     
  2. Hoople

    Hoople Account Removed

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    The only useful meter checks for a VR is when the VR is dead shorted. Then it will tell you something meaningful=> it is dead shorted. On something like what you have (intermittent charging output), meter checks are almost useless. Bad diodes would never be intermittent.

    You have done your homework. You have checked just about everything you can check or tighten.
    Most likely the front end of the regulator has a problem. There are a bunch of discrete components in the regulator that steer, regulate and direct the output of the stator that you just can't check with a meter. The fact that the lights dim supports what your seeing on the meter is real.

    Nothing is 100% proof positive but it sounds like a bad VR to me.
     
  3. Lancer

    Lancer Junior Member

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    Thanks Hoople, I'm leaning towards the VR myself. Wanted to see if any others had experienced anything similar. Intermittent issues are always a royal pain.

    Lancer
     
  4. TQuentin1

    TQuentin1 Well-Known Member Staff Member Moderator

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    I would always defer to Hoople, but in this case I suspect the same thing. That is the way my VR began failing. Then it finally just quit charging and I was running on battery only. Just made it home with the battery voltage at around 9Vdc on the dash meter!! Pure luck!!!

    But it might behoove you to check out the stator while you are doing this. I mean open up the Primary and look at the stator itself. Any burnt coils, and I would swap out that puppy too.

    TQ
     
  5. Lancer

    Lancer Junior Member

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    TQ, Thanks for the input, looks like it might be time to install that SE compensator that I've been putting off.

    Lancer
     
  6. Lancer

    Lancer Junior Member

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    Installed new VR, everything working as advertised. Since it was intermittent to begin with only time will tell. Nice crack in the bedding of the old one, could be where issue started.

    Lancer
     

    Attached Files:

  7. JamesRClark

    JamesRClark Member

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    It's been a few months...any updates?
     
  8. Lancer

    Lancer Junior Member

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    Have not had any issues since I replaced the VR.
     
  9. smartguy

    smartguy Member

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    Lancer, more info? More input, more input. How much $$, How hard to do? Did you do the work yourself?... Thanks
     
  10. Lancer

    Lancer Junior Member

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    Paid $127.00 for the part. (Components Plus) Replacement was easy, 2 bolts, 2 connectors. Took about 10 minutes, (takes me half that to get up and down off the floor) :(