temp sensor plays no part in fan operation, the sensor is located on the back of the thermostat housing, a small fitting, with a wire fed thru a "faston blade connection"; it only effects the actual gauge reading.
The actual fan switch, is the one on the left bottom side of the radiator, this controls the "on/Off cycle" of the fan, and is dictated by it's own temperature controlled switching within that device.
The fuse, is the single one, in a single White plastic "fuse holder" adjacent/attached to the J box, It also controls the clock features on early models. some changes within the lighting, and J box changed in '94 but basically everything else remained the same.
easy check of the actual fan and power, is to wrap a paper clip around thee 2 pins (with wires still attached)on that fan switch, shorting them together, the fan should run regardless of temperature when the bike is on.