brake light problem HELP!!!

Discussion in 'Softail Models' started by lc45276, Sep 24, 2011.

  1. lc45276

    lc45276 New Member

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    lead will light up tester light but will only light up the element a very little on a new bulb,both of the elements work fine when hooked up to the running light lead. any suggestions thanx
     
  2. dangerdan

    dangerdan Junior Member

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    I would check for a solid ground. If thats good then measure the voltage.
     
  3. speedyron

    speedyron Active Member

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    sureits the right bulb?
     
  4. Hoople

    Hoople Account Removed

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    Where are you placing your "tester light"? At the tail light socket? Does it happen with both the front brake lever and foot switch or just one?
     
  5. UGSBUE

    UGSBUE Member

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    "Does it happen with both the front brake lever and foot switch or just one?"

    That's a VERY good question from a diagnostic point of view:

    My FXSTC Rear Brake (foot) did not light the brake-light whilst the Front Brake (hand) did. It's a common problem with the hydraulic brake switch that uses brake-fluid pressure to light the brake-light when the Rear Brake (foot) is applied.

    I replaced the switch and for curiosity i tested the impedence on the old one. In an 'open' condition the resistance should have been infinite, however there was a measureable impedence indicating that the switch was not completely 'open'. Thus some current was flowing. Perhaps, if you discover the situation i did, some current is flowing and thus it lights you tester but the total current is insufficient to illuminate the brake-light filament.

    Answer the first question and go from there - diagnostically speaking.
     
  6. bikerdad

    bikerdad Junior Member

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    My vote is a bad ground. Run a wire from the negative of the socket right back to the battery negative terminal. If the light works, this will prove it. Then, start checking ground connections all the way back to the battery. I have had this same problem on bikes and cars.