I have a hampton bay fan. The remote is working for the fan portion, the upper light, but not the lower light. The red light on the remote does not light up when pressing the button for the bottom light. Any way to fix this?

If you press the remote button and see no red light it is likely a bad remote. While nearly everything can be repaired a remote is usually not worth the effort. Have you tested the light socket?

You can try taking it apart and cleaning the buttons, or order a replacement remote from the manufacturer.

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