Rear brake light wiring, which one?

Antek

.040 Over
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Apr 21, 2021
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2020 Rocket 3 TFC
Folks,

anyone know which of the three wires going to the rear light is for the brake light?

I took a volt meter yesterday and found the black center to be the negative wire no problem, and I believe the yellow wire to be the running rear light, however the green wire which I’d gue to be the brake light never showed any voltage even when I pressed the brake.
 

TURBO200R4

stand up straight and grab the world by the a$$
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I am going to guess u r having trouble with your brake light.
Will it work when appling thr front brakes.?
Will it light when appling rear brake?
U can take a fused wire and apply to green wire to check system.
If not getting voltage i would guess a bad brake switch.
 

G-Force Junkie

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I was considering adding an aftermarket brake light for safety by splicing into the brake signal line, but was concerned a change in resistance on the line may trigger faults in the computer. It does not appear to be as simple as 12v thru a mechanical switch to a thermal flasher relay, to in incandescent bulb with two tits like in the old days. :) Today, the timing of the flashers is controlled by a computer. If I was at my bike...I would try it again with the bike in running mode, i.e. perhaps the brake signal is disabled if not running:).
 
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TURBO200R4

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I can not see it making a difference.
I would first try a 12 volt test light and see how that works. Also test light works good to check the circuit /bulb
If the test light works then i would think that the extra light would work.
 

Antek

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Ok so that didn't work :( the brake light wire is not the real 12V power source of the brake light... back to the drawing board find a clean solution.
 
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