Grab your ground from the battery, fused positive from battery going to your isolator other connections should be solid ( I hate those blue clip together deals ) either soldered and heat shrink or a plug in kit with solder and heat shrink, by the way did I mention I HATE those little clip deals that are the source of a lot of wiring issues.
Next check your bulbs and make sure they have a good clean solid connection, some dielectric grease will help keep things from corroding. If you are using LED's on the bike side that may also cause an issue for you. Should not be a problem on the isolated circuit.
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