Quoting transparentdsm:
the oval one by the thermostat housing is for the a/c fan, the coolant temp sensor is on the bottom of the rad, unless you dont have a stock rad and the CTS has been moved to a different location.
the CTS wiring is located on the 6 pin connector that controls the main fan for the cooling system and the wires are black and green, both are solid and they will also be the two skinny wires. same oval connector at the end as the one by the thermostat housing though.
Wanted to clarify this. The oval one is the ECT sensor that the ECU looks at(AKA, the important one). The one in the radiator is the radiator fan switch. The single wire connector is for the gauge in the dash. The white 2 pin in the top of the housing is for the AC system.
Wiz