1996 Toyota Camry radiator fans

The primary fan on my sons Toyota will not come on and stay on. I checked the fan #1 relay and when I pull the relay 1/2 out you could hear it clicking and the fans would come on and run. When you push it in the fan shuts off. We replaced the relay. Same thing. I removed the relay and bypassed it completely with a wire and it ran fine. The 2nd fan would not run at all either. When I bypassed fan #2 relay I heard a pop and now the relays won't even click and I can't get either to turn on. I suspect a temperature switch inline somewhere in the car. Where would it be and how would I check that. Any ideas/ Thanks! Steve