LED Turn Signal Lamp Replacement

[catfishk]

i replaced the center gauge on my GS450E with two lights, one green neutral LED and one yellow turn signal LED, screwed into the back of the headlight housing (yes, i got the idea from whichever of you cafinaters pointed out you can get these from Radio Shack with a built in resistor!). the neutral lamp works great! and i *thought* the turn signal LED did, as well, so i took off riding proudly
however, it only flashes one way! i simply spliced the two wires to the original lamp when installing the LED. i am assuming if i were to swap the leads it would only flash the other way, though i haven't tried yet. anyone know how i might correct this?

[robertbarr]

it only flashes one way! i simply spliced the two wires to the original lamp when installing the LED. i am assuming if i were to swap the leads it would only flash the other way, though i haven't tried yet.

If that works, why not just install a 2nd LED, with the polarity opposite of the first? They are diodes, after all. That would allow current flow in either direction, which is what a bulb's filament would do.

Just supposing...

[catfishk]

yeah, maybe i'll just pop another next to it. have the original harness wires split to each LED, and with independent grounds. i'd think all it has to do is ground out...
i'll have to get another yellow LED and try it out tomorrow...

[Steve]

I the original configuration, when the left signals are 'hot', current also flows through your panel bulb and 'grounds' to the hot lead of the right side signals. There is not enough current going through the panel bulb to light the right side signals. When the right side signals are on, the panel bulb 'grounds' to the hot lead of the left side signals. The original bulb works with either polarity.

Your LED panel bulb only works in one direction. If you wanted to maintain the simplicity of one LED, you could install diodes between the signal wires and the LED. Attached is a diagram showing the difference in the two circuits. I did not bother showing the flasher, the switch, or other stuff, just the turn signals and the panel bulb.

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[catfishk]

so- since the light only acts in one direction, and not both like the original bulb, it will work either way but only one at a time. i can therefore wire in diodes, which i assume will restrict current in a particular direction depending on which way they are installed, to both sides of the new LED accordingly and it will make it light somehow? i see in your diagram i need to add another ground, or maybe... ugh i am confused now.

can i purchase a couple diodes from Radio Shack? i'd like to play with this a bit, even though it is totally unnecessary as i can see the front turn signals while riding

could i split the two pig tails of the original harness to two LEDS, one for the right signals and one for the left, with independent grounds and have the circuit complete in either direction?

[Steve]

so- since the light only acts in one direction, and not both like the original bulb, it will work either way but only one at a time. i can therefore wire in diodes, which i assume will restrict current in a particular direction depending on which way they are installed, to both sides of the new LED accordingly and it will make it light somehow? i see in your diagram i need to add another ground, or maybe... ugh i am confused now.

can i purchase a couple diodes from Radio Shack? i'd like to play with this a bit, even though it is totally unnecessary as i can see the front turn signals while riding

could i split the two pig tails of the original harness to two LEDS, one for the right signals and one for the left, with independent grounds and have the circuit complete in either direction?

OK, evidently you have the two original wires connected to the two leads of the LED. Remove them, but keep them handy. Yes, you can get basic diodes from Radio Shack. Nothing special about them, just generic diodes. I don't remember what numbers you might need to ask for, might be something like 1N9004. The diodes will have two leads, one of them will come from the end that has a band around it. Connect the end without the band to the leads from your turn signals, connect the end with the band to the other diode, again, the end with the band. Here you might need some test wires. Connect one end of your LED to ground, the other to the joint between the two diodes. Turn on a turn signal. Does the LED flash? If not, switch the leads around, connect the other lead to ground and try again. When you get it to flash, wire it in permanently.

Yes, you could do independant lights, but if you already have a hole drilled in the headlight bucket, the second one would not be symmetrical. This is just an idea to keep you from drilling an off-center hole.

Not as hard as it sounds, hope this helps. 8-[


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[catfishk]

ok, i see where i confused myself. i'll be waiting at Radio Shack's door tomorrow morning to get my diodes! and you're right, that is the way i had it wired; the way the original bulb was configured

i didn't want to drill the new hole, i was only curious if it would work that way for the sake of understanding the concept

thanks steve!

[catfishk]

i wired the diodes in exactly as you described, and the light flashes with both sides now. works and looks great! thanks steve!

funny, it is getting harder and harder to stuff all the wiring into my headlight housing these days...

[Steve]

Your 450 might have a 6" headlight?

Other models have 7", and some even have an 8". :shock:

Should be PLENTY of room in them. 8-[


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[catfishk]

well, i deleted the center instrument cluster. it was broken in two places and bounced around while riding. the fuel gauge didn't really read properly and the whole unit looked sort of wonky regardless. so, naturally, i shoved all that wiring, including the gear position lamps , into the headlight bucket. i will properly unwire the stuff when i do a winter overhaul