Topic: Both turn signals flashing

[AtlTech]

78 CB750F running LED signals with the 3 prong novita electronic flasher and a separate indicator light for each signal (R and L). Thought I had everything done right, but now activating either the R or L signals makes every blinker on the bike flash. The switch is testing fine. Any guesses as to what I can do to fix this issue? Apologies if I missed a previous thread on this, but no one seems to have had this issue while running 2 indicator lights.

[bryanj]

Disconnect the repeaters and see what happens, frequently led and "normal" bulbs dont play together well.

[Bodi]

The only link betwen sides should be the single indicator on the dash, make sure that is disconnected. It plays hell with leds. The leds work on a few milliamps, and it takes very little leakage between sides to light both.

What is a repeater?

[Dolomite]

You may need to use a pair of diodes anywhere there is shared power. I had to use them in my rear lights as well as in my pilot light when changing it to a single indicator. I used 10a50v ones from amazon. Just be sure to test them before making the connections permanent so you know they are the right way.

[Bodi]

10A!!!  IMO A 1N400X (X is voltage spec, 1N4001=100PIV etc) 1A diode is more than enough and easier to deal with than a 10A type, solder wire to the leads and cover it with shrink tube.
You should not need diodes though since you have separate idiot lights. Diodes are needed with all-LED indicators for a single idiot light.
I don't know where the left and right circuits can connect... the obvious place is the single idiot light but you have removed that, presumably.
Maybe the switchpod is somehow leaking current between the signal outputs? If you have markers, maybe there is a wiring error with them that somehow does it? Using a normal bulb connected to one side and flashing the other, you will get an idea how good the cross connection is - flashing bright means there is a good solid cross connection, no or almost no glow from the filament says the cross is leakage: maybe in the switch or where the single idiot light connected.

[Dolomite]

They share a common wire at the rear harness, since the stock lights had their grounds coming from the stem itself. Same in the front but with the nuts securing the bucket.

And 10a diodes were used because they are on the same circuit as the 10a fuse, ie if a diode were installed that rated for lower amperage than the fuse then the diode may fail without proper cause.

[AtlTech]

Thanks for the replies, all. I followed the first suggestion, bypassed the flasher relay and then set to work with the multimeter. Found out my headlight bucket (the bucket itself) was getting 12V pushed through it. A bit more investigation and I learned that apparently one of the wires on my turn signals connects the turn signal housing itself. So power was going from Relay -> Switch -> Right Turn Signal Wire -> Right Turn Signal Housing -> Headlight Bucket -> Left Turn Signal Housing -> Left Turn Signal Wire. By switching the wires that connect the bulbs to the turn signal switch and ground, I was able to beat the problem. I'll attach a picture of how I had it wired in case that helps anyone who encounters this problem.


Pic Link:
https://drive.google.com/file/d/1Zs8H1nmATlQAxdr7iD1WhI3i1gzwxIer/view?usp=sharing

[Bodi]

"And 10a diodes were used because they are on the same circuit as the 10a fuse, ie if a diode were installed that rated for lower amperage than the fuse then the diode may fail without proper cause."
Fair enough, however if something in LED turn signals draws 10 amps a blown diode is not your biggest problem. And a 10A fuse won't in fact protect a 10A diode in a dead short situation, the diode will be toast before the fuse blows: you can get very fast acting diode protect fuses but nobody would use them in a bike - they cost about 10x normal fuses (and blow really easily).

Dual filament (or LED dual brightness) signal wires, especially aftermarket signals with wire colors not the same as standard Honda colors, can be confusing. They should be checked carefully to confirm what each wire does. It's easy to check with a battery and decide that the ground is a power wire... the bulb will be bright and dim depending on where the power is applied, just as expected: except it's wrong and if the housing also grounds the socket you have a one-shot fuse tester. LED dual brightness lamps should not do that because LEDs only work in one polarity.

[AtlTech]

except it's wrong and if the housing also grounds the socket you have a one-shot fuse tester.

Definitely tested my fair share of fuses. They all worked haha. Glad I made the switch to the blade-style fuses. The glass tubes were just too annoying to get in the proper size.