Cant find what sensor or switch turns on cooling fan for kawasaki vulcan 800 classic

If it follows the rest of Kawi's line-up, (and it probably does): 5 wire?!

Brown=Ignition
White= Battery
Gray=Ignition
Blue=Taillamp 1
Red=Taillamp 2

Brown is for things that need to be energized, like the rad. fan, etc.
Gray is for the ignition/ignitors themselves.
Connecting white, brown and gray should get you going. Add blue for lights.

Red, together with white is for parking lights.

sending unit on engine no good .try this un plug sensor and jumper across plug end and see if fan come on if so positive sensor defect.change sensor.

Sit at a traffic light till the temp reaches about 220, it should start about then. My fan has come on 3 times in 8 years.

It can be the Heat Sensor or there is not enough Water in the cooling System and the sensor Gives Signal to cool down with switching on the Fan .

The following wiring diagram applies for Kawasaki VN800 Vulcan motorcycle series. Herein you will find complete and clear description of ignition switch, radiator fan switch,temperature sensor, radiator fan, handlebar switches, rectifier, speedometer, headlight, spark plugs, tail brakelights, signal lights, alternator and battery.http://www.mediafire.com/?eztezdedw0n

test or replace fan switch thermostat and flush cooling system