Ceiling fan light works with wall switch, but... I have a second hand Hunter fan with no

Question

I have a second hand Hunter fan with no instructions. I have a black, white and red wire in the ceiling box. I connected the fans wires in this way: black/white stripe to white supply, white to red supply, and black to black supply. The light works correctly when I flip the wall switch but when I use the pull chain to turn on the fan, the light comes on dimly on the first pull, a little dimmer on the second pull, and not at all on the third pull. The model number I found on the fan is 21721.