Tail light wire issues
Are both element's in the bulb ON?
Reason: sometimes individuals break the brake light switch tip when changing grips, levers or handle bar.
Switch works backwards of common button.
out is ON and pressed is OFF.
Keep in mind we can not see your project and only have your words to work with.
"At first yes??? the front brake would turn light off??" What does this mean to you?
"The two wires coming off TAIL LIGHTS"..Does the bike have one tail light or more than one tail light since you used the word LIGHTS?
How were the two wires incorrect?
What did you fix and how did you fix it?
The tail light generally has two wires and ground.
+ for running light...one filament of 1157 bulb stays ON
+ positive when brake is activated...on a dual filament bulb like an 1157 the second filament will light if brake is activated
negative-/ground is a constant.
The metal barrel portion of bulb is negative-/ground.
The two nipples on bottom of bulb will be separate positive connections.....one for + running and one for + brake.
Put power first to the green then to the red and see what the tail light does.
Then check voltage at the blue and the red with and without the brake activated.
The wires to the rear all come from a molex plug under the seat and a plug on the backbone under the tank from the bars.
Time to start tracing wires, has a run/brake, turn module been added, those green and red wires look non OEM?
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BE/BK is 12V from 15amp circuitbreaker and runs to taillight
The two red wires are 12V comming from stoplight switches and going into red to the stoplight bulb
Now check if you have 12 V at the orange wire at the stoplight switches and if you have 12V at the acc circuit breaker
If you have 12V at the circuit breaker and the stoplight switches, activate the stoplight switches and check if you have 12V at the read wires of the stoplight switches
Last edited by FXD2003Rider; Jun 8, 2025 at 07:21 AM.








