Toyota Repair: 98 toyota camry radiator fan, engine radiator, radiator fan

Question
One of the fans on the radiator comes on when the air conditioner is turned on. the other doesn't, even though the car is overheating. I tested and the fan works with direct power, I am replacing the radiator (it blew) and the thermostat. what relay switch controls the fans? Inside the fuse box I have spots for Fan 1, Fan 2, and Fan 3.Or could it be the switchon the bottom of the radiator? And how can I tell?

Answer
There are different fuses for the different fans,one fan is when the A/C runs, the other runs based on engine / radiator temp..  You may have a bad temp switch which is not telling the fan to start.  You need an electrical diagram for your vehicle and trace the lines, which are color-coded.
Hope this helps.
Vince