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I had to replace one of my turn lights. and I can't figure out the wiring. The way I have it set up right now, the light will get brighter, but it will simply stay bright until I shut it off, instead of blinking the way it obviously should. Additionally, the rear signal doesn't do anything either (though I suspect the two problems may be related). I have the wiring diagram but I can't make heads or tails of it. What can I do to fix it?

I ride a 1981 CX500, if it helps.
 

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I take it it was a front indicator you replaced? the rear that doesn't blink is on the same side? the other side works ok?
 

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We need some more info. What type of light did you get for the front? They are two filament bulbs if stock incandescent. The fronts are always on as running lights until the turn signal is initiated. Then they flash. Check your flasher relay, probably under the right side cover, any standard relay should work for stock set up. The rear lights do not light until a turn signal is initiated, as designed. Most places it's illegal to have rear running lights except for the main tail light.

If you went to an LED, then the can of worms is different. There are many threads/posts here regarding this matter, so try the search or look in the WIKI (link below)

Joel in the Couve
 

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Did you replace the signal light with an LED type or an incandescent? Also, is it a two-wire or three-wire signal? Many replacement signals assume a chassis ground, so that if it comes with two wires it's really a three-wire design using chassis ground as the virtual third wire. Did your new light come with any sort of circuit diagram? You can run simple tests to answer these questions if you have an ohmmeter. Or let us know if these questions cause you to gasp for air.:)
 

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<edit removed>

It could be there isn't enough draw to trip the relay, and the reason I asked if the opposite side works normally would be to rule the relay out. but my guess is he has the drl wire attached and not the turn signal, or if they are both attached, he may have them backward, the dlr being IIRC a lower draw filament.

edit again: If the rear indicator does nothing, are you sure the bulb is good there? As I mentioned above, if one light is out, the other will just stay on and not flash as there isn't enough current to flip the breaker (flasher). If your front light gets brighter when you turn on the signal, that should indicate it is coming on..... I assume your gauges indicator goes on and stays on as well? I'm pretty certain your problem is at the back not the front. Ground or bad bulb....
 

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I had to replace one of my turn lights. and I can't figure out the wiring. The way I have it set up right now, the light will get brighter, but it will simply stay bright until I shut it off, instead of blinking the way it obviously should. Additionally, the rear signal doesn't do anything either (though I suspect the two problems may be related). I have the wiring diagram but I can't make heads or tails of it. What can I do to fix it?

I ride a 1981 CX500, if it helps.
if you are using incandescent bulbs then check the wiring. i just replaced my turn signals with some and the manufacture had the wrong wires labeled. if one side is getting brighter and not flashing you might have a positive wire grounding to the frame. when i had my wires switched up the "ground wire" was actually a positive wire so it would make the turn signal light up super bright and mess all the electronics up. aka my break light was flashing for some reason. once i took the light apart and figured out the ground was a different wire it started to work properly. One wire should be your power. the second wire should be will send electricity to the back turn signal and the third is ground. I believe its labeled orange and white and orange on one side and blue and white and blue on the other side. make sure those are correct as well. All this is for incandescent bulbs though. if you bought LED bulbs you will have to put some resisters into your wiring because they use a very small about of electricity and it won't work properly.
 

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Never, ever add resistors to male LED turn signals flash. That is like putting a band aid on a broken leg. The correct solution is to install a flasher that is designed for LEDs. It will probably cost less than the resistors and you won't be wasting power heating up resistors.

Jay:
We need to know whether the replacement signal is an original type or something aftermarket (& if it is why didn't you replace both so they match?). Also, if they are aftermarket do they have 2 wires or 3 (the originals have 3). Once we know that we may be able to offer better help.

In the meantime, lets start with some basics:
1) The original front turn signals on these bikes (& most Hondas of the same era) function as both running lights and turn signals. They have the same dual filament type 1157 bulbs that are used in the tail/brake light. The lower power filaments are used as marker lights so they are on normally. When you switch a turn signal on the low filament in that bulb is turned off and the high power filament flashes so that you have BRIGHT-OFF-BRIGHT-OFF (if the low filament was left on you would have BRIGHT-DIM-BRIGHT-DIM).
Amber marker lights are only allowed at the front of a vehicle so the rear turn signals do not have marker lights.
2) Turn signal flashers generally need a certain amount of current flowing through them to make them switch on & off and that is usually more than one bulb draws.
3) All electrical circuits must be connected to both sides of power to work. If you connect a light bulb to the battery's + terminal (either directly or through the bike's wiring & switches) it won't light unless there is a path for current to get back to the battery's negative terminal.
4) Grounding to the bike's frame is not very reliable and grounding to the forks or triple clamp will require current to pass through the steering head bearings which can cause them to fail prematurely due to sparks happening inside them. The ground connection must always connect to a green wire in the wiring harness.
5) The filaments inside an 1157 bulb are connected so that one side of each goes to its own contact on the end of the base and the other side of both are connected together to the metal shell, which is supposed to be connected to ground.
 

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Discussion Starter #8
Sorry I haven't been responding to anyone, I thought I had myself set up to get emailed when receiving responses. I was wrong.

The light is a K&S 25-1105C with two wires. The reason I didn't just go ahead and replace both is that I had the part ordered from a shop, and I took the mechanics word for it that it was the same. In hindsight, probably a bad idea.

The rear indicator on the same side is the one that isn't working properly. The other side works perfectly fine.

I'll try all of the rest of the advice in this thread and see what else I can do. Thanks for all of the responses!
 

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OK, I think I have it figured out. The specs for that K&S signal say it has a dual filament bulb but it only has 2 wires. That means that it must need the housing grounded for the ground (common) connection. As I mentioned before that is not a good way of doing things. I would recommend making sure that there is a wire connected to the signal's mounting point that connects to a green wire in the bike's harness.

Once you have the housing grounded, momentarily connect each of the signal's wires to the orange/white or light blue/white wire (depending on whether you are working on the left or right signal) and observe which one lights the signal more brightly. Connect the bright one to the orange or light blue and the other to the orange/white or light blue/white. Your new signal should work now.

If the signals on that side still don't flash and the rear one does not light that means that either the rear signal is not connecte4d or its bulb is dead and there is not enough current to make the flasher work.
 

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Ok so I think I went through the same issue with my bike. You need to find another Flasher relay that works with the watt requirements
EMGO makes a cheap 12v/10W flasher relay 7 bucks off ebay item number 66-86722

If you are using the same factory relay... they are rated for 12v/23W bulbs. Your new signals wont blink because you don't have enough resistance. Just get a new 2 prong flasher relay and you should be good to go. On your new signals, check out the bulb imprints and see if they say 10 watts

Good luck! :)
 

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Your new signals wont blink because you don't have enough resistance.
Well to start with, that's wrong. If there is too much resistance not enough current will flow to make the flasher work. If you don't have enough resistance some flashers might flash faster but it it won't keep them from working.

Just let him try the stuff I suggested and see if that works instead of jumping in with something else. Trying all sorts of things at random is not the way to solve problems. Going through the steps logically is.
 

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Logic???? C'mon.....random is best.

Alway work systematically. Work the simple, most probable to the complex least probable. 9 times of 10, the problem is simple fix that was caused by a probable issue.

In this case, its likely lack of wiring diagram leading to mis-connections, faulty bulb or poor ground. My bet is on mis-connections.

Follow Bob's instructions.
 
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