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LED stoplights 900

posted by  someone claiming to be Ira Eisenberg on  Tue Jul 14 08:22 CST 2015 [RELATED]

Installing LED bulbs as stop lights seemed like a good idea because they are very bright and illuminate almost instantaneously. However, doing this caused the bulb failure lamp on the dashboard to illuminate every time I touch the brake pedal. The LED bulbs are working properly.

Any idea why this would happen and any suggestions for a fix. Thanks








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    LED stoplights 900

    posted by  B.B. on  Tue Jul 14 08:46 CST 2015
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    last visit: Mon Oct 6 13:15 CST 2014
    [RELATED]

    The bulb out sensor is designed for filament bulbs
    I switched to LED bulbs and disabled the bulb out sensor legs involved
    with brake lights and head lights etc.
    I suppose that you don't need a bulb out sensor with long lived LEDs

    Bill








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      LED stoplights 900

      uid 27's pic
      posted by  Art Benstein on  Tue Jul 14 09:00 CST 2015
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      last visit: Fri Oct 17 20:10 CST 2014
      [RELATED]

      Yes, exactly.

      Although the right and left brake lights would balance at any current, the BFWS circuit was modified in '86 (long before there were 940s) to accommodate the high-mounted center lamp. This extra circuitry specifically looks for incandescent lamp current.

      Disabling the BFWS is a mixed blessing. True enough, diodes themselves should last longer than the car, but unfortunately that does not mean the lamps will light up more reliably, through all the supporting connections needed, than the filament type, and therefore not need monitoring.
      --
      Art Benstein near Baltimore

      We childproofed our homes, but they are still getting in.








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        LED stoplights 900

        posted by  spasske on  Tue Jul 14 09:50 CST 2015
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        last visit: Thu Oct 23 10:11 CST 2014
        [RELATED]

        Is there an LED bulb available for the high mount break light that would balance out the currents to make the bulb out relay not pick up?

        I suspect in a 3 LED replacement, one missing bulb might not be enough current imbalance to pick up the reed relay in the bulb out sensor so it may not be useful any more for brake light failure detection.
        --
        Paul NW Indiana '89 744 Turbo 180K/ '90 745 turbo 145K







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