Coolant Sensor Switch Location

[chaaur2]

My 81FC35 electric clutch fan will not engage unless I apply 12 volts
directly to the fan wiring. I suspect the problem is the thermostat
switch, But I can not locate this switch on the engine. Does anyone
know he location? When tracing the wiring from the clutch fan the power
wire connects to two additional wires. Does anyone have any idea where
these wires are coming from? I guess one is coming from the thermostat
switch.

Thanks
Charlie Shannon
Saint Albans, WV
81FC35