the first one was pined down right beside washerfluid tank since i got the car, and i believe it was never plugged in with anything the line bundled up with all the headlight wires going above radiator toward driver side i blieve
when u say primary cooling fan, are u talking about the fan behind the sidemount intercooler?
that plug is for the sensor that would be in the washer fluid bottle if that was an option in the mazdaspeed trim. It was cheaper/easier for mazda to make one harness for all proteges so that plug sits dormant. You might have had that option in Canada if you have a warning light for low washer fluid.
i mean theres already 2 plugs connected to the fluid bottle, 1 for the pump and 1 for the sensor (and that sensor is alraedying telling me low on fluid today, cause i took the fluid reservoir off to mount FMIC and not much fluid left in)
i dont know if thats a sensor, but theres 2 connector connected, and its showing in my dash that i have low fluid level, so it must be a fluid level sensor or something alike