For some reason my car only fan only when ac is turn on. Most of the time the fan never run and usually boil up the radiator cap. Recently i disconnect the bottom radiator engine coolant temperature sensor wire and it would run since then. Yesterday i use the paper clip to test the bottom one and the one on the driver side. It would run so my problem is that i changed from the themostat,and both coolant sensor. What can be wrong with it

 

Lexus es300 1997