Where is the thermostat for the rad fan located?V6 engine

 

Follow the upper radiator hose to where it connects at the top of the engine (usually at the intake manifold) the hose should connect to a "housing" that has either 2 or 3 bolts holding it down. Remove the bolts & the thermostat should be inside that housing. To access the bolts, you may need a swivel adapter or swivel wrench. Now if you are referring to the "sensor" that sends the signal to turn the electric fan on, it's located at the rear of the engine in the passenger side exhaust manifold, in front of the "cowl" area.