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I was hoping.someone could help I have a 2003 yamaha vstar 650. I just recently replaced all the lights with led lights. Now all 4 flashers blink when i use them turn signal. My brake light turns on but doesn't brighten when I hit the pedal. The only light that seems to work is the headlight. Any help would be appreciated
 

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American Legion Rider
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My first thought is you need to add some kind of resistance to compensate for the lack of incandescent draw but I thought that was normally hyper flashing. You did nothing but change bulbs? Sounds like you might have cross a wire somewhere. I'd put the incandescent back in first just to prove they work, then change one set of lights at a time. Like just the rear or just the front directionals. I'd expect hyper flashing but then your bike might have an electrical system that tries to compensate too. But prove they work first, then go from there. Changing to LEDs is not always plug and play. It can get very irritating depending on the machine.
 
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Ghost in the machine
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Is it possible that the brake light bulb is not correct and the flashing turns are to let you know you have a bad brake light set up? Much the way incandescent bulb systems in cars flash faster to let you know when a filament is burned out. just a thought.
 

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MOD / Rider / Mechanic
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I agree with both of these, had similar issues converting my Goldwings over. For the turn signals you will need to add resistors. The brakelights are very hard to get correct and visible and I decided it was too much and left mine incandesent. So many of the LED uses Internal resistors and bypass circuits to make brighter instead of separate LED's makeing so many of them dangerously not bright enough. My reasoning today compared to 5 years ago with conversions is I tour now. If I am out and something burns out I need a shelf item to fix it, plug and play without question. Then I was at home or close and could wait.
 
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In many bikes, the indicator on the 'dash' is connected to both sides, thus connecting them together. With regular bulbs, the current demand on the off side lets them act as a ground to the indicator. Even if you replace the indicator with a bidirectional LED, it conducts enough to light the LEDs on the off side. I put two of the regular bulbs, one on each side, back on my old CB450 to stop this; didn't want to mess with splicing into the nearly 50 year old wiring.

Tail/stop light is another problem, but shouldn't be related to the turn signals.
 

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I ran into this when I converted my Vstar 650 to LED turn signals, here is the fix, works 100% perfectly but it does take a little bit of wiring to add the diodes.

http://www.650ccnd.com/pdfs/VStar650DiodeMod.pdf

I know Radio shack is pretty much no more, you can get same or similar diodes on ebay or amazon for a dollar a dozen so you'll have plenty of spares.

I also changed the flasher to a LED type one to cure the high speed flashing after putting in the LED bulbs but that part is easy, though on the Vstar when you do this you lose the auto cancel feature ( that most other bikes don't have to begin with anyway)
 

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I don't have any experience with a problem like this, but I have an idea which may help.

Regular bulbs don't care which way positive is coming from. You can't get it wrong. LED's DO care though. The long wire is the positive and the short wire is the negative on a single LED which would go into a bread board.

My point is that if it is as one pointed out that the off bulbs actually ground the other bulbs, but those LED's or the previous LED's were backwards, then they could possibly all turn on. Maybe on one side of the bike switch the wires and see if that works as the polarity of the LED, which is also a diode, that's what the D in LED means.
 

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I don't have any experience with a problem like this, but I have an idea which may help.

Regular bulbs don't care which way positive is coming from. You can't get it wrong. LED's DO care though. The long wire is the positive and the short wire is the negative on a single LED which would go into a bread board.

My point is that if it is as one pointed out that the off bulbs actually ground the other bulbs, but those LED's or the previous LED's were backwards, then they could possibly all turn on. Maybe on one side of the bike switch the wires and see if that works as the polarity of the LED, which is also a diode, that's what the D in LED means.
Sounds good, but no. The LED bulbs are connected only one way, and that is with the positive on the center conductor (or conductors, in the case of the front bulbs), and negative on the outer shell, assuming 1156 or 1157-style bulbs. It's just that very little current is required to make one glow, less than what the flasher indicator will conduct. The 'off' side will be dimmer than the 'on' side, but not a lot, even if the indicator has been replaced with a LED too. The solution is the pair of diodes as illustrated above, or putting two of the filament bulbs back in. A typical turn signal filament lamp is ~21W when on, which is about 1.6A at ~7.5 Ohms, but that's hot. When cold, the filament is about 1/10 the resistance, or 0.75 Ohms, close enough to look like ground to the little 5W bulb used for most indicators. Now, replace that filament with an LED, which doesn't conduct until the Voltage rises over about 2V, at which point it starts to glow; it doesn't take much power through the indicator, even a LED one, to make the off side light up, because full brightness is reached at about 0.25A, probably less, and the indicator probably conducts about 0.1A.
 
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