Have you checked to see where the brake signal is coming from? If its from one of youre lower lights(and i suspect it is) youre converter wont work right. On the "bike side" the brake signal needs to come from youre 3rd brake light. Theres a port in youre center trunk that is used to add a 3rd brake light on youre trunk. That is the wire you want to use to get youre brake signal to youre pigtail. Check that and let me know what you find. I had a 5 to 4 converter on my gl1500 and it worked perfectly and thats how it was wired.
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