I think I need to change the thermostat switch, But I can't find it, any help out there ?? Thanks

Cooling fans that run constantly could be either a sticking relay (under hood, in a rectangular box by the driver side fender) or the temperature switch (I think it is located at the bottom corner of the radiator - not sure. If not, check around the thermostat area on the engine for a plug with a two wire connector.)

You can check if it is the relay simply by replacing the relay for the cooling fans with another from the relay box (note: The part numbers of the relays in that box should all be the same and swappable).