Good holiday-decor question — answering as the UphillTech team:
If you incorrectly wire a ceiling fan and a light fixture by putting the fan in series with the light, then the light will come on bright until the fan gets going, at which time the light will become unusably dim. Fan and light must be wired in parallel . Turn off the power, go back to the wiring diagram that came with the equipment and correct your connections. If it looks right to you, get another set of eyes on it or edit your question by adding a clear, closeup, well-lighted photo of your wiring. To add a photo, click EDIT then use the sun and mountains icon.
Full answer by MTA: https://diy.stackexchange.com/a/305841 (CC BY-SA 4.0).
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