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Discussion Starter #1
Ok, an issue I can't seem to resolve happens to be with my blinkers. I can only get the front blinkers (or) the back blinkers to flash. One thing I noticed while the ignition is on is the Front blinker lights remain dimly lit as if they were running lights. It will flash normally when switched either right or left. Think the issue can be with the flasher? I'm pretty sure there should be no power running to the blinkers while the bike is running unless the blinker button is pressed.

-Cahuna
 

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The front signal lights are supposed to be dimly illuminated even when the signals are not activated.
 

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Do both your front & rear winkers flash when you flip switch to left or right?

If so, then everything's Ok. Front should be always on as running/marker lights when bike is on.
 

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Discussion Starter #4
Do both your front & rear winkers flash when you flip switch to left or right?

If so, then everything's Ok. Front should be always on as running/marker lights when bike is on.
Funny, but I can only get the front blinkers to work. The rear ones do not. Looking at the wiring diagram, they should all be running on the same circuit together. Rear blinkers were connected to an integrated LED tail-light but they stopped working when I installed the front blinkers. I'm usually pretty good at sorting out electrical problems but this seemingly easy fix has me puzzled.

-Cahuna
 

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Ah... not factory lights. Are the front 3-wire lights?

May also have to install ballast-resistors in parallel with each LED bulb.
And get solid-state flasher relay that works with LED bulbs.
 

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Discussion Starter #6
Ah... not factory lights. Are the front 3-wire lights?

May also have to install ballast-resistors in parallel with each LED bulb.
And get solid-state flasher relay that works with LED bulbs.
No, front are 2-wire from the factory, standard bayonet bulb blinkers. I tried the resistor trick but it didn't work (I forget the result when adding the resistor). I remember looking for the flasher relay some time ago but it was a weird 9-pin device that only Honda CBR's run. I think it may be my 9-pin flasher that's the problem. I'll take it out and check for corrosion and clean it if necessary. Maybe I can find a way to test it.

I did detach the rear LED blinkers and connected them back to the standard bulb-type blinkers. They still didn't light up or flash.

-Cahuna
 

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Resistors should be installed in parallel with LED bulbs, not in-line. Much better to add to LED lights before connecting to bike. Adding it afterwards can be troublesome because there's 4 wires involved instead of 2. If adding afterwards, best to remove LED light completely from bike to add resistors. Resistors only connect to LED bulbs and not to factory wiring in any way.



If you just unplug front bulbs; does rear work?

I did detach the rear LED blinkers and connected them back to the standard bulb-type blinkers. They still didn't light up or flash.
Ok, so problem is with wiring then. Work backwards and undo changes made to wiring. Did you cut original wiring in harness?

Here's connectors that fit into orginal harness. Put these on LED winkers first. Then it's just plug-n-play to connect to harness to leave it unaltered. Then much simpler to go back to stock bulbs for troubleshooting by just unplugging:


Post photos of all 4 winker connectors at factory harness. Something's not connected like original configuration. We want to restore back to 100% factory condition before moving forward.
 

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Personally, I don't think the problems with the front and back signals are connected. You say the rear signals were once connected to an integrated LED taillight. You can get the front ones working, but not the back. It's easy to mess up the wiring in the tail when adding a mod and you're doing it for a second time. I think you should grab a multimeter and concentrate your investigation on the back of the bike first.
 

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Hey, that's good idea. Testing with multimeter always saves tonne of time scratching your head!

1. Did you restore factory tail-light and brake-light ?
2. Does factory tail-light and brake-light work properly?

Given: ALL 4 bulbs at rear share common ground wire (green).
TESTS - remove all 3 bulbs from sockets so you can probe terminals in bulb-sockets:

1. measure resistance between tail-light ground (green) and battery negative. Ohms = ???
2. measure resistance between brake-light ground (green) and battery negative. Ohms = ???
3. measure resistance between left-winker ground (green) and battery negative. Ohms = ???
4. measure resistance between right-winker ground (green) and battery negative. Ohms = ???

5. key ON, measure voltage at tail-light terminal (brown) relative to battery negative, volts = ??
6. key ON, brake-lever squeezed, measure voltage at brake-light terminal (green/yellow) relative to battery negative, volts = ??
7. key ON, turn-signal switch LEFT, measure voltage at left-winker terminal (orange) relative to battery negative, volts = ??
8. key ON, turn-signal switch RIGHT, measure voltage at right winker terminal (lt.blue) relative to battery negative, volts = ??
 

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Resistors should be installed in parallel with LED bulbs, not in-line. Much better to add to LED lights before connecting to bike. Adding it afterwards can be troublesome because there's 4 wires involved instead of 2. If adding afterwards, best to remove LED light completely from bike to add resistors. Resistors only connect to LED bulbs and
not to factory wiring in any way.



If you just unplug front bulbs; does rear work?

Ok, so problem is with wiring then. Work backwards and undo changes made to wiring. Did you cut original wiring in harness?

Here's connectors that fit into orginal harness. Put these on LED winkers first. Then it's just plug-n-play to connect to harness to leave it unaltered. Then much simpler to go back to stock bulbs for troubleshooting by just unplugging:


Post photos of all 4 winker connectors at factory harness. Something's not connected like original configuration. We want to restore back to 100% factory condition before moving forward.
Danno, is the drawing below correct? That the main difference between the two circuits is the current that falls on the diode? In circuit (II) a negligible current and therefore it will not heat up, nor burn?
 

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Danno, is the drawing below correct? That the main difference between the two circuits is the current that falls on the diode? In circuit (II) a negligible current and therefore it will not heat up, nor burn?
View attachment 45302
It's actually opposite. When you have parallel circuits, each one operates independently and draws its own current regardless of other. Let's back up and look at single circuit 1st, say only front winker light. First, specs on factory winker bulbs is 12v 21w

We'll use these equations Watts=VI and Volts=IR
21w=12v*I
I=21/12= 1.75 amps
12v=1.75*R
R=12/1.75= 6.86 ohms

So factory winker bulbs have 6.86-ohms resistance and when powered by 12v, draws 1.75-amps for 21-watts consumption. Idealised, if you actually measure resistance of bulb, it won't be 6.86-ohms when cold, but it will be when filament heats up to operating temps. Right-front winker circuit looks like this, it draws 1.75-amps for 21w consumption.


Now, what would happen if we connected another winker light to bike, say… for right-rear? In Y-split configuration...


It would make sense that each circuit would draw 21w on its own? And “trunk” wire that feeds both circuits would have to supply double power 42w? To simplify in schematic-drawing, we would combine both into parallel circuit, each one consuming its own 21w independently from each other.


Independent and separate is important because you can disconnect either one and it won’t affect other in any way. If you pull rear winker-bulb out, front would still work.

Same if your front winker-bulb died, rear would still work.

It's like they have their own wires going directly to battery. Such as adding fog-lights to your bike or heated-grips. Each circuit is separate and independent of any other parallel circuit already on bike. Each additional circuit you add, results in more power-consumption...

It’s actually possible to calculate how much current is flowing in trunk wire that feeds multiple parallel circuits with:

So we know resistance of 1st circuit = 6.86 ohms. Second circuit using same bulb would also be 6.86 ohms.

R1 = 6.86 ohms, R2=6.86 ohms
1/Rtotal=1/6.86 + 1/6.86 = 2/6.86 = 1/3.43
Rtotal = 3.43 ohms

Let’s calculate current-draw and power-consumption:

V=IR, 12=I3.43
I=12/3.43 = 3.50 amps

W=VI, W=12*3.50
Watts = 12*3.50 = 42 watts

We see that effective or equivalent resistance of parallel circuit is lower than either one individually. This is resistance if we replaced both 21w bulbs with single 42w bulb. Battery and trunk wire won’t care if it’s 2x21w bulbs or single 42w bulb. Resistance (equivalent) is same and identical 3.50-amp current would flow.

Parallel circuit makes sense? Really important to get this before we move onto why LED bulbs needs ballast-resistors and how to wire them up properly.
 

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It's actually opposite.
ok
I read, understandable and clear, the maestro can continue? ... please.
The parallel connection of a diode to an LED diode aims to lower resistance, and attract more current?
 

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Now let’s see what happens when we replace factory bulb with LED. Most 1156 LED bulbs consume about 2-watts.

We'll use these equations Watts=VI and Volts=IR to calculate current-draw and resistance.
2w=12v*I, I=2/12= 0.167 amps
12v=0.167*R, R=12/0.167= 72.0 ohms

We see that power-consumption is only about 10% of earlier with factory bulbs. This lower 0.167a flow through factory flasher-relay results in hyperflashing due to less physical heating of flasher’s bi-metallic strip. Ballast resistors can be used to increase power-consumption and heat up flasher-relay to factory levels. However, most people install resistors incorrectly using series/in-line circuit. Problem is, this actually increases total resistance of circuit and lowers power-consumption, not increase it. We can determine final power-consumption by calculating equivalent/final resistance of series-circuit with:

Rballast = 6 ohms, Rled = 72.0 ohms
Rtotal = 6+72.0 = 78 ohms
V = IR, I=V/R, I = 12/78 = 0.154 amps
Watts
= VI = 12*0.154 = 1.85 watts

We see that total power flowing through series/in-line circuit with ballast-resistor installed is LESS than original circuit with LED bulb alone! Because current-flow is less, flasher-relay heats up less and hyperflashes even FASTER than before without resistor. Additionally, since same 0.154a current has to go through both resistor AND LED bulb, it has to divide its power between them, resulting in LED being dimmer than before. This resistor in series/in-line with bulb is how traditional dimmers work, it takes power out of circuit before arriving at bulb, thus making it dimmer. We can actually calculate how much that 1.85watts of power is distributed:

VoltageDrop = IR
VDres = 0.154 x 6 = 0.924v
Wres
= VI = 0.924 x 0.154 = 0.142 watts used by resistor
VDled
= 0.154 x 72 = 11.1v
Wled
= VI = 11.1 x 0.154 = 1.71 watts used by LED

With resistor in-line with LED-bulb, it drops voltage by 0.9v and “robs” LED of power entering it. LED now only gets 11.1v input instead of original 12v and it glows dimmer than before using only 1.71w. We don’t want series/in-line circuit!
 

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ok
I read, understandable and clear, the maestro can continue? ... please.
The parallel connection of a diode [resistor] to an LED diode aims to lower resistance, and attract more current?
Yup, that's correct.
Here's proper way to connect ballast-resistor for LED-winkers is with parallel circuit independent from LED itself. To determine final power-consumption:

Rled = 72.0 ohms, Rballast = 6 ohms
1/Rtotal=1/72 + 1/6 = 13/72
Rtotal = 5.54 ohms

We'll use these equations Watts=VI and Volts=IR to calculate resistance and current-draw
12v=I*5.54, I=12/5.54 = 2.17 amps
Watts=VI, w=12x2.17 = 26.0 watts

We can also determine individual power-consumption of each individual circuit in parallel configuration.
LED bulb = 12 x 0.167a = 2w which we already know from before
Ballast Resistor = 6 ohms
V=IR, 12=Ix6, I=12/6 = 2.00 amps
Watts=VI, w=12x2.00 = 24 watts

The ballast-resistor on 2nd parallel circuit consumes 12 TIMES power of LED-bulb itself! Total consumption of 26-watts is higher than 21w of original incandescent bulb. For what? A dimmer bulb! If you wanted brighter bulb, it’s so much easier to just get higher-output incandescent bulbs. Plug-n-play with absolutely ZERO wiring needed.

Eiko 1295 - winker bulb - 610 lumens, you will NOT find LED winker bulb brighter than this
Wagner BP3496 - brighter tail & stop-light bulb
 

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Dimmer LEDs because I have yet to find any LED bulb that's brighter than factory OEM winker bulb. Certainly not as bright as the Eiko bulb I linked to above.

So you want to find resistor that will result in equivalent power-consumption as stock 21w bulb? Calculations are correct, very good! :)

Typical engineering practice is to have double capacity of actual usage. So 19w consumption should use 38w resistor minimum. Here's popular supplier: Power Resistors - Ohmite Mfg Co
 

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So you want to find resistor that will result in equivalent power-consumption as stock 21w bulb? Calculations are correct, very good!
No, at the moment you are the teacher and I am the student. I practice to learn.
Typical engineering practice is to have double capacity of actual usage.
Now I understand why you need the aluminum monster with the heatsinks(y):cool:

I saw that it usual supplies at 25W, 50W 100W ...
So for my calculation I need:
WH50 7.5R 1%?
aluminum resistor is "WH"?
I have seen that it can be found in all sorts of names when the keyword "aluminum" is in everyone.
Is there a professional name for this component?
This is a 50mm long monster...
 

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If it helps, I used an 6 ohm resister and it didn't work.
Resistors didn't work for getting winkers to flash? That's wiring problem.

Properly installed resistors will only lower flashing-rate of already working properly wired winkers. If they're not flashing at all, resistors won't affect or fix that in any way.

Fix wiring first so winkers flash, probably too fast. Then install resistors to slow down flashing.

1. Did you restore factory tail-light and brake-light ?
2. Does factory tail-light and brake-light work properly?
Did you measure and test your rear bulb sockets? This is 5-minute fix with multimeter because it'll pinpoint exact problem area instantly. It'll be very obvious, like lion chewing on your leg! Can't miss it!!
 

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Discussion Starter #20
Resistors didn't work for getting winkers to flash? That's wiring problem.

Properly installed resistors will only lower flashing-rate of already working properly wired winkers. If they're not flashing at all, resistors won't affect or fix that in any way.

Fix wiring first so winkers flash, probably too fast. Then install resistors to slow down flashing.

Did you measure and test your rear bulb sockets? This is 5-minute fix with multimeter because it'll pinpoint exact problem area instantly.

Can't wait to try. It's been raining but as soon as it dries up I'm going to head out there and start testing.
 
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