The radiator cooling fan or your fan for the heater and air conditioning? If it is the fan for your heater and air conditioning it could be several thing. The most common problems are the blower...
If it doesn't blow at all, and/or you only feel a small amount of air coming through the vents (not forced), it may be the blower motor switch.
I changed out mine for under $10. The local dealer...
If NONE of the brake lights are working (including the "high mount" center light, I'd check the stop light switch next. It is located up under the dashboard near the top of the brake pedal lever....