The car is overheating. I replaced the T-Stat which seemed bad (didn't open in a pot of boiling water). The radiator and one fan were replaced in the past 2 years. Now, both fans are not working. I was told there is a fan switch/sensor in the T-Stat housing, also one in the water outlet goosneck, and possibly one in the radiator. Can anyone tell me which one switches on the fan so I don't end up replacing the wrong part. Thanks.