Please Help me Wire my 1157 LED's into a OEM 2 Wire Turn Sig

Discussion in 'The Garage' started by Shoganai, Nov 13, 2012.

  1. Shoganai

    Shoganai Let's do some livin'

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    #1
  2. sailah

    sailah Lampin' it

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    If the OEM turn signal has only a ground and hot, you won't get running lights without running another wire from your harness that comes on with running lights. Unless I don't understand the diode situation, which I don't:lol3

    The resistor is used simply to generate enough of a draw to activate the electro mechanical switch in your blinker module. Easier to just replace that module with one specifically designed for LEDs. I have one on both my bikes and it's literally plug n play. If you do that you don't need the resistor which is a bad solution to the problem. Since I don't know what kind of bike you have can't give any actual products but if you google LED blinker relay (your bike) you should come up with one. I got one online and the other at cycle gear.

    So if you run a running light wire from your harness to the lead on your LED for running lights, hook the flashing lead for each side up to the signal prong on the LED and buy a LED flasher relay, the wiring is much more simple.

    I have no experience with your bike so if any of this doesn't apply to BMWs can't help ya.:lol3
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  3. Grinnin

    Grinnin Forever N00b

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    You certainly don't need a blocking diode on the running light wire.

    If a bike has a single light on the dashboard that serves for both directions, then you may need blocking diodes. If your dashboard has one light for left and another light for right then you're OK.

    IF you have only that single dashboard turn light, you'll need to:

    1. make a new ground for the dash light
    2. run each of the turn-signal wires going to the dash indicator through a diode (silver or white band toward the dashboard)
    3. connect the output of the two diodes into the non-grounded side of your dashboard turn light.
    Sailah is right that the resistor works but an electronic flasher is a better solution. Search for "solid-state" or "LED" or "low-load"

    Your flasher could be 2-prong or 3-prong no matter if it is electromechanical or solid-state. IF you replace a 2-prong flasher with a 3-prong flasher all you have to do is connect the third prong to ground.

    I'll stop now, but you may need to look at what your bike has and ask for more details.
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  4. ScEd

    ScEd Dances with Deer

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    You will need to pickup the running light with a new wire. If this is on your BMW the rear will be easy to pick up from the tail/running light. The resistor would wire parallel to the load (one lead from the resistor to ground and the other to the + or hot to the bulb. A 50-watt resistor would be huge so its possibly a 50-Ohm x 5-watt but not sure where the value you stated come from. What is the reason for the change to the LED's? Just curious as I may want to do the same on my RT lol.
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  5. ScEd

    ScEd Dances with Deer

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    Look's good to me.
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  6. Grinnin

    Grinnin Forever N00b

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    Shield? To me the word "shield" is a metal wrap to prevent electromagnetic interference (like radio waves coming off your ignition wires).

    Do you mean insulate? Fuse?

    Your logic sounds very good, I don't want a powered wire running around loose either, but we don't have the same terminology.
    #6