Hey all,
My '94 Civic overheated yesterday and I noticed my radiator fans didn't come on when they were supposed to. My radiator fans come on when turning on my AC, though.
I am suspecting it could be the coolant temperature switch or 'thermoswitch', but have also read instances where it could be the thermostat itself. I'm curious if anyone here had the same experience and if so, could it be the thermoswitch or the thermostat?

 

Unplug the fan switch (you called it the thermo switch) found on the thermostat housing... with the key on and engine off, bend a wire or paperclip into a "U" shape and connect the two female pins of the fan switch plug together... if the cooling fan system works, the fan will come on. If not, you have another issue with the system: Short or open in wiring, blown fuses, bad relay, bad fan motor, etc.