[gilz1945]

2018 Goldwing DCT with Honda trunk spoiler run/brake harness and modulator. Have had for it several months with no problems but today the running light stopped lighting up. Brake light modulates but no running light. Any ideas... thanks

 

[laen]

You probably fried your computer with some aftermarket tail light modulating harness not designed for the bike. Just because you can buy aftermarket products does not mean it will work properly with Honda's complicated CANBUS system,\. Then again it does not mean it won't. Happy hunting.

 

[Drair]

Pull out the modulator and try it again. My '08 had a reputable brand of tail light modulator that just died, and the wing LEDs no longer worked at all.
Also, check carefully for a pin pushed out of the connector in one of the couplers. It might not be obvious.
You might have done that when you installed the modulator but it took a while for it to act up.