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I found out that the bulb had gotten moisture into it and it was shorting out, I got a new bulb and seal and it fixed the issue. I’m glad it wasn’t any wiring problem though.Either the filament broke and fell over onto the other filament, or you have a two-filament bulb jammed in a single filament socket, you have two wires shorting, or the two filaments share a ground that is broken off and it's backfeeding and finding a ground somewhere else.