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  1. #1
    CB750 Member Milanb's Avatar
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    81 CB750c blowing turn signal fuse LED

    Hi I replaced all of the original blinkers with led ones (led strip light in the rear, and bar mount led in the front) on my 81 cb750 c. As soon as I hit the turn signal switch the turn signals just start to flash when the main (turn signal/brake light) fuse blows. Does this sound more like a ground out problem or a load resistor needed problem. I've heard that there could also be a grounding issue in the turn signal switch itself but im not sure where to start.
    Thanks,

  2. #2
    CB750 Guru amc49's Avatar
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    You can have a grounding issue in virtually every inch of wiring if it is defective.

    'Does this sound more like a ground out problem or a load resistor needed problem.'

    The problems are virtually the same as the exact same thing happens, the fuse blows because power flows too easily. So, question answered still means nothing. If the LEDs do not have built-in resistors you MUST add it to them, not doing it will burn the LEDs out pretty quick (as fast as instantaneously). You may not have enough resistance and the fuse may be saving the LEDs by popping. On 12 volt you need a roughly 680 ohm resistor to produce ample lighting, lesser amounts to get the brightness up more like for signals, lower than that LED life drops like a rock.

  3. #3
    CB750 Member Milanb's Avatar
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    Ok so I put in a different brand of the 15 amp (turn signal/brake light) fuse and I got 2 flashes out of the system before it blew. But the flashes seemed fast which I think generally narrows it down to the resistor install. Where should I install the resistor, I've seen one for each light on cars but I feel that's excessive, can I put one for each pair of lights (front and back) or one in front of the relay?

  4. #4
    CB750 Guru amc49's Avatar
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    One resistor per light simplifies things as far as understanding, changing that forces you to determine arbitrary resistance requirements. Clearly making more trouble for you. Resistor goes just before the light.

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