Electrical guru help please
Club Member
Joined: Sep 2010
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From: Beyond Fucital
Are you sure that the turn signal module will be able to handle the load driving two filament bulbs (F-R) at the same time without the rear brake/turn signal combination module? It wasn't designed to do that so there may be an issue there because that is what those modules are for.
Last edited by RANGER73; Sep 20, 2016 at 08:58 PM.
Grand HDF Member
Joined: Mar 2010
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From: South of Mordor
I am wondering what is going on with the OP's harness. I can't find or remember earlier models having a blue w/ color stripe wires built into the harnesses. What it sounds like is he has obtained a newer harness much like the one in the pic below. OP, can you confirm, or maybe better yet provide a pic of the connection where the harness plugs (7B) into it mating harness under the seat. I would like to see if the colors of the wires are the same on both sides of the harness plug. The harness pictured below allows for the stop/turn (blue with stripe) and run (blue) function to be applied. If I am correct, you have a newer harness at this point, but when plugged into the stock harness it most likely won't work as planned. I really need a visual of what we are working with to confirm some information.
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From: Beyond Fucital
I do believe that when my old stock tail (stop/tail/turn) lights went out (using dual element bulbs), I either had both brake and turn light function but no running or had running and lost brake/turn. Pretty sure one element is made for 12v which both the turn and brake supply and the other element only gets 6v for the run element.
I am wondering what is going on with the OP's harness. I can't find or remember earlier models having a blue w/ color stripe wires built into the harnesses. What it sounds like is he has obtained a newer harness much like the one in the pic below. OP, can you confirm, or maybe better yet provide a pic of the connection where the harness plugs (7B) into it mating harness under the seat. I would like to see if the colors of the wires are the same on both sides of the harness plug. The harness pictured below allows for the stop/turn (blue with stripe) and run (blue) function to be applied. If I am correct, you have a newer harness at this point, but when plugged into the stock harness it most likely won't work as planned. I really need a visual of what we are working with to confirm some information.
I am wondering what is going on with the OP's harness. I can't find or remember earlier models having a blue w/ color stripe wires built into the harnesses. What it sounds like is he has obtained a newer harness much like the one in the pic below. OP, can you confirm, or maybe better yet provide a pic of the connection where the harness plugs (7B) into it mating harness under the seat. I would like to see if the colors of the wires are the same on both sides of the harness plug. The harness pictured below allows for the stop/turn (blue with stripe) and run (blue) function to be applied. If I am correct, you have a newer harness at this point, but when plugged into the stock harness it most likely won't work as planned. I really need a visual of what we are working with to confirm some information.
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From: South of Mordor
Your probably correct about the 12v, I've never really looked into the voltage part of the system. I have always strictly gone off of wiring schematics and paths taken for sources when building my harnesses for my bike. However, it doesn't change what I proposed about the way the signals are sent to the bulb, one element for the run signal and the other for either the brake or turn or a moldule/computer controlled combination, which is how the diagram shows it routing. What the diagram didn't show was where the signal comes from, does it come from a module or straight from the main harness and computer controlled and that's the info we need to solve the issue the OP wants to solve.
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From: Beyond Fucital
Your probably correct about the 12v, I've never really looked into the voltage part of the system. I have always strictly gone off of wiring schematics and paths taken for sources when building my harnesses for my bike. However, it doesn't change what I proposed about the way the signals are sent to the bulb, one element for the run signal and the other for either the brake or turn or a moldule/computer controlled combination, which is how the diagram shows it routing. What the diagram didn't show was where the signal comes from, does it come from a module or straight from the main harness and computer controlled and that's the info we need to solve the issue the OP wants to solve.
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From: Beyond Fucital
The center tail light is a dual filament bulb for run and brake. The OP has run turn strut lighting and run brake fender light. He if he wants the blinkers to function as brake lights too he needs a separate module.
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From: Texas
I was thinking of an older stock Dyna setup. The turn signal module doesn't mix the turn signals and brake lights are a separate circuit altogether. That is the purpose of the brake/turn mix module. I was thinking there may be an issue with the extra load on the brake circuit or current leak through the single filament turn signal bulbs. Weird **** can happen when you modify light circuits
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Club Member
Joined: Sep 2010
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From: Beyond Fucital
Sounds like you have it all figured out.
I was thinking of an older stock Dyna setup. The turn signal module doesn't mix the turn signals and brake lights are a separate circuit altogether. That is the purpose of the brake/turn mix module. I was thinking there may be an issue with the extra load on the brake circuit or current leak through the single filament turn signal bulbs. Weird **** can happen when you modify light circuits
I was thinking of an older stock Dyna setup. The turn signal module doesn't mix the turn signals and brake lights are a separate circuit altogether. That is the purpose of the brake/turn mix module. I was thinking there may be an issue with the extra load on the brake circuit or current leak through the single filament turn signal bulbs. Weird **** can happen when you modify light circuits