Sometimes the fan comes factory with no light, they will sometimes throw in a pull chain to control the wires that would have been for the light, then when you get a light to put in it will have a pullchain on it for the off chance there is no pullchain to control it on the fan fixture itself. or it could be the reversal switch for the direction of the fan.

 

Some of the ceiling fans I have see with third pull chain that useally resverd for the revering switch so it can run the fan foward or reverse.

Due some case the housing or design prevent to use the conventianl switch they used the pull chain to do this function.

Merci,
Marc

 

Well....sorted it out. As it happens, there's a 3rd light (an upper tier light) in the upper canopy of the fan. When lit, the light shines through the venting in the side of the fan motor....kind of a night light.
It is not even mentioned in the instructions or on the packaging.
Would have been easier to figure out but for the wiring harness for the light kit was defective. I ended up cutting the light feed out of the harness and splicing it directly to the light kit. Voila! Works like a charm.
Who knew there was a night light? The homeowner was very proud of his purchase.....wait until he has to change the bulbs in it....3 screws per light access, 4 bulbs....accessed from the top of the fan motor assembly.
Thanks for your help guys!