Topic: LED Turn signals

[exf5003]

I've been doing some research about this topic and found a great source from a thread back in the day. Bodi explains the different flashers but specifically spells out which one to get for LED lights (see below).
I first got a LED replacement bulb for tail/brake light and rear turn LED signals (Not replacement bulbs) with incandescent bulbs in front. I put in his recommended flasher and things worked perfectly. Now I'm replacing the front signals with LED's  like my rear turn signals, but when i put a turn signal for left or right, they all light up all at once nice and bright. All other lights work as they should. With my limited research, do i need to install resistors? If so any recommendations? i hate working on electrical system  .
Thanks in advance

Bodi

Re: Electronic flasher for LED's
« Reply #4 on: October 24, 2006, 09:13:07 AM »
The type we want has ground, power, and signal terminals. The power to make it flash is independent of the lamp power draw. Most SOHC4 bikes have a loose green ground wire hanging beside the flasher, this is perfect for connecting a 3-terminal flasher.
Looking at a rack of flashers at your local Pep Boys it's hard to tell which 3-terminal flasher is the right grounded type and which is the other type which will just blow a fuse if you try connecting it with a ground wire. The electronic type is better than the thermal type, it uses less power and has a constant flash rate as it ages.
The easiest way to know you have the right one is to find one with the terminals numbered. These numbers are a JSO or DIN (not sure which) standard, I haven't been able to find a list of what the numbers mean but they are consistent.
You need a flasher with the terminals numbered 31, 49, and 49a. If you see these numbers, you have the right one! Other numbers means it is the wrong type.
The green (ground) wire goes to #31.
The black wire (+12V) goes to #49.
The other wire (to turn signal switch) goes to #49a.

[bjbuchanan]

You need diodes. It is the Tsig indicator bulb backfeeding and lighting them all. With incandescent the ganged lights don't matter but led they light up. Put a diode between both or and and blue to your dash common

[Mr Freeze]

Give this a try. I also bought LED signals and a No Load flasher relay and hooked the relay up with the new signals and all 4 would light up just like yours. Then I switched the 2 wires (not ground) from the relay that plug into harness and they flash like they should. Sounds like a polarity issue with the new relay as compared to the old one.

Your power and signal wires need to be reversed.

[exf5003]

Give this a try I bought LED signals and a No Load flasher relay and hooked the relay up with the new signals and all 4 would light up just like yours. Then I switched the 2 wires (not ground) from the relay that plug into harness and they flash like they should. Sounds like a polarity issue with the new relay as compared to the old one.

Mr Freeze- so you just switched the black and gray (mine is gray, yours could be different) on the flasher relay? I'm not sure mine is a "No Load Flasher" I just looked for the relay to have the 31, 49, & 49a numbers as Bodi described. It only says Electronic Flasher for LED.
I'll have to give this a try after work. Would be amazing if i didnt have to put diodes in as bj has indicated. I'll report back either way.

Put a diode between both or and and blue to your dash common

bybuchanan-  I cringe at messing with this stuff and excuse my lack of knowledge with this. If Mr Freeze's simple fix doesnt work i'll have to put the diodes in, but your statement confuses me. Do I only need to put diodes in both turn signals? and what is the blue to the dash common? Have a link to the diode I need by chance?

Thanks guys.

[Duke McDukiedook]

I found the easiest way to get my flashers to work was go with LED on the front for power savings since they were on all the time and incandescent on the rear since they only come on when I flip the winker. Works fine here so far.

[Sticky Gerbil]

I have front and rear LED flashers. I used a $12 "electronic flasher". Normal flashers work with resistance causing a thermal switch to throw. LEDs don't provide enough resistance to trip this type of switch, but the electrical flasher uses a chip instead of this. My lights would not flash until I installed this flasher. Available at any auto parts store.

[exf5003]

I found the easiest way to get my flashers to work was go with LED on the front for power savings since they were on all the time and incandescent on the rear since they only come on when I flip the winker. Works fine here so far.

Only reason I switched to all LED was because my one front incandescent turn signal lost the orange cover on one of my rides. I've been wanting to replace them because they stick out too far with clubman bars, so now was a great time to change them up.

I have front and rear LED flashers. I used a $12 "electronic flasher". Normal flashers work with resistance causing a thermal switch to throw. LEDs don't provide enough resistance to trip this type of switch, but the electrical flasher uses a chip instead of this. My lights would not flash until I installed this flasher. Available at any auto parts store.

I have both of these, but they both make all my signals come on at the same time.
http://shop.advanceautoparts.com/p/tridon-novita-tech.-inc-electronic-turn-signal-flasher-ep35/5081297-P?searchTerm=electronic+flasher
http://shop.advanceautoparts.com/p/tridon-novita-tech.-inc-electronic-turn-signal-flasher-ep36/5081335-P?searchTerm=electronic+flasher

[bjbuchanan]

It isn't too complicated but I'm pretty positive that the set of diodes is the solution to your problem. The reason switching the wires worked for the other guy was because it was wired backwards, you fixed it.

The normal setup uses the blue and orange to the dash light. The bulb that isn't working works as a so-so ground through the unused filament and bulb housing, as I understand it. That's how come two power wires make the dash circuit work despite the lack of a traditional ground

I'm no wizard with a soldering iron but I trimmed the edges of the diode, stuck them in to the copper wires, twisted and soldered. Did the trick for me. There are people who run an incandescent inline to act as a resistor which is baffling to me, instead of one light you now have two sucking power, however little that may be. Some day that bulb will fail too...

The easiest fix with no fiddling is running incandescent on the rear like Dukie. All the power savings but much less hassle especially if you are uncomfortable with the changes

[Mr Freeze]

Someone else has said it, a flasher for LED's implies it's a "no load" type of unit because LED's don't draw enough current to make a stock flasher unit work. You shouldn't need diodes because is doing the switching (on-off-on-off to blink). Anyways, in my harness (1978) the wires going to the flasher relay are Gray and Black and the flasher unit happened to also have Gray and Black wires coming off it, which doesn't mean anything because the they weren't labeled which was power and switched. Their color coding and Honda's are just different that's all.

Anyways, the colors in your harness may vary, but it seems likely that you have the POWER and TURN SIGNAL SWITCH wires going to the wrong terminals on the new relay. The way it works is that there's always power at the relay and when you flick the turn signal switch left or right, it connects the power to one side (LEFT lights) or the other (RIGHT lights) and allows the relay to flash the power on and off. A polarity reversal on the relay causes the light to stay lit solid just like a headlight or running light. You can see it right in the schematic all the black wires have 12V all the time and the various switches turn those lights on and off (Neutral, Oil Pressure, Headlight indicator, etc.)

Check this schematic out to verify your harness colors. They don't say which colors go to which terminals on the relay, so try switching the black and gray wires on the terminals of your new relay.

http://www.cycleterminal.com/wpimages/Honda-CB750K3-K7-Wiring-diagram.jpg

[exf5003]

Anyways, the colors in your harness may vary, but it seems likely that you have the POWER and TURN SIGNAL SWITCH wires going to the wrong terminals on the new relay. The way it works is that there's always power at the relay and when you flick the turn signal switch left or right, it connects the power to one side (LEFT lights) or the other (RIGHT lights) and allows the relay to flash the power on and off. A polarity reversal on the relay causes the light to stay lit solid just like a headlight or running light. You can see it right in the schematic all the black wires have 12V all the time and the various switches turn those lights on and off (Neutral, Oil Pressure, Headlight indicator, etc.)

Well i just tried this out and when i switch my black and gray wires (have a k4) i get nothing, no flashing or clicking from the electronic flasher, when putting turn signal on left or right.  My green is ground and that should remain on the prong labeled 31. Your explanation provided insight for me with what goes on but not so lucky with getting it to work. I tried switching the wires on both relay's and i get nothing from the turn signals. All other lights come on.
Do you know what electronic flasher you are using?

It isn't too complicated but I'm pretty positive that the set of diodes is the solution to your problem. The reason switching the wires worked for the other guy was because it was wired backwards, you fixed it.

The normal setup uses the blue and orange to the dash light. The bulb that isn't working works as a so-so ground through the unused filament and bulb housing, as I understand it. That's how come two power wires make the dash circuit work despite the lack of a traditional ground

I'm no wizard with a soldering iron but I trimmed the edges of the diode, stuck them in to the copper wires, twisted and soldered. Did the trick for me. There are people who run an incandescent inline to act as a resistor which is baffling to me, instead of one light you now have two sucking power, however little that may be. Some day that bulb will fail too...

bjbuchanan- I just looked up diode in amazon and of course they have a million different ones with different Amps and Volts. Any insight on which one is safe to use?
Thanks

[tlbranth]

i hate working on electrical system  .
Thanks in advance

Bodi

Brings to mind a sign an engineer posted at Hewlett-Packard when I worked there in the 60's:

If God had meant man to manipulate electrons, He would have made them easier to see

[bjbuchanan]

I may have been wrong about the need for the diode, I needed it with my led dash. When I ran my just LED signals I used 1/4 watt resistors and they tripped the lights. These were tee'd off my output of the handlebar switch, the blue and orange that come out

Now I do have diodes set up for the LED dash light to function properly, but may have not needed it originally without the dash. I did it in steps and don't remember exactly when the diodes made an appearance but thinking about it they shouldn't be necessary

At radioshack they have resistor packages, just match up the 1/4 watt ones, its like 2$ for 8 of them. Splice in to the wires and you are good to go.

[exf5003]

I appreciate everyones input. I'm going to have to try my cheapest option first and put some resistors in first. BJ, would i need to put resistors for my back LED's as well as my front turn signal LED's? or just front?
Thanks again for all the help.
Hope everyone has a great and safe holiday!

[Mr Freeze]

 I tried switching the wires on both relay's and i get nothing from the turn signals. All other lights come on.
Do you know what electronic flasher you are using?

Do you have multiple relays for the turn signals? Explain that part.

I bought this relay. You can see it is a 2 wire unit and bought based on the recommendation of someone on this forum. You don't HAVE to have a ground on the relay as long as the turn signals you installed have a metal body, they'll ground through the frame. It you did get a 2 wire unit you'd just have an extra ground in the harness which isn't a big deal. Here's the relay

 http://www.superbrightleds.com/moreinfo/motorcycle-accessories/lf1-s-pin-universal-motorcycle-electronic-flasher/193/841/

[Bodi]

OK I am confused. What do you mean by "they all light up all at once nice and bright"? Do the left signals all light up when you select left, or do all four - left and right - light up? These are different problems and I assumed the latter when I first read it. The diode fix addresses the "all four signals light up" problem, and only applies to a bike with one "signal" idiot light in the speedo/tach; not an issue on bikes with left and right idiot lights.
If it's only one side and your problem is that the lights come on but don't flash, it is a flasher issue. I don't have flasher model numbers that work, there are so many different models that I can't guess which ones are good for LEDs. Adding load resistors will probably work. You only need one resistor per side.
It should work without resistors if you get the right flasher - those available from some of the LED signal lamp suppliers, at least, should work. Even a 3-terminal electronic flasher needs a bit of load current to activate the flashing function so it isn't clicking the flasher relay all the time. It's a trial and error thing to find a stock auto parts store flasher that will trigger on the all-LED power load. I have opened the case and changed resistors in  a flasher module to get the normal flash speed with LEDs (with low load they go to a different flash speed to indicate - in a normal application - that a turn signal lamp is burnt out) and it should be possible to change something inside to lower the "start flashing" trigger current as well but that's a major PITA.

[Honda550k]

Here's an easy and free fix for all those having a flashing rate issue when installing led signals. Install a non signal light in the line of the front signal lights and just hide it in the headlight. I did that. 10000km after still good. I am also using a non led relay. Just a electronic one from a auto store.

[tlbranth]

Here's an easy and free fix for all those having a flashing rate issue when installing led signals. Install a non signal light in the line of the front signal lights and just hide it in the headlight. I did that. 10000km after still good. I am also using a non led relay. Just a electronic one from a auto store.

Kinda defeats the purpose doesn't it?

[exf5003]

Well after being away for holiday weekend and finally getting back from traveling for work I was able to go and first try installing 1/4W resistors and then 1/2W - 22 Ohm resistors with absolutely no luck.  I first placed the resistors on the front 2 LED turn signals and then on all four LED turn signals and the exact same thing happend as before for both cases. All signals light up and blink at the same time (imagine having four-ways on blinking).
Is the 22Ohm still to small of resistance?

OK I am confused. What do you mean by "they all light up all at once nice and bright"? Do the left signals all light up when you select left, or do all four - left and right - light up? These are different problems and I assumed the latter when I first read it. The diode fix addresses the "all four signals light up" problem, and only applies to a bike with one "signal" idiot light in the speedo/tach; not an issue on bikes with left and right idiot lights.

I attached a pic of the LED flasher that I have. When i connect them as you describe(green-ground 39; gray 49a; black 49+) all four led turn signals light up and blink at the same time and I can hear the flasher clicking. I have a 74 750 with one signal idiot light, so I'm assuming I need a diode from what your saying.
Now for the dumb questions... How do I install the diode?
Is this what I should be installing?  http://www.superbrightleds.com/moreinfo/car-install-supplies/metric-bike-diode-kit/1190/ I'm confused with the diagram, what is the black rectangle that both left and right connect to? In step 2 it shows the right turn being grounded?

 I tried switching the wires on both relay's and i get nothing from the turn signals. All other lights come on.

Do you have multiple relays for the turn signals? Explain that part.

Sorry for the confusion, I have the relay i attached and i also bought another  model EP35 from same manufacturer, its the only two they had with the numbers Bodi mentioned so i bought both and tried what you mentioned for both relays (one at a time). I'm not that incompetent
Switching the gray and black (with ground) gave me no flashing at all. Taking the ground wire out resulted in very very dim turn signals staying on (not flashing). I'm assuming this flasher does not work for what you did to yours.

Thanks for the link to your relay. I have it in my cart as i type this, but i was really hoping the resistors would work.

[exf5003]

bumb 

[Mr Freeze]

I checked out that relay you bought, it still isn't a "no load" relay. Your LED signals that are installed may still not be enough resistance to make the EP35 relay work. Consider using a 1K 1/4 watt resistor inline and see where that gets you. Either that or get yourself a no load relay. Motorcycle turn signals are significantly smaller than those for a car and an LED signal is going to have such a small current draw that the relay won't click the power in and out because there isn't enough resistance present to make the relay do what it should.