Fan not coming on...overheating

I have a 91 toyota camry that has started to overheat when at lights..idling..etc
We came to the conclusion that our radiator fan is not kicking on...we hooked it up direct and fan does come on. Also the a/c fan isn't working and our a/c was blowing cold air up until now...but today it is not. I don't know if being low on freon could make the a/c fan not come on. we have changed out 2 of the fan relays still nothing..
looked at the blower motor and it is working. anything else to try?

It sounds like a bad sending sensor unit to the electric coolant fan.

There is a fan coolant temperature switch located in the bottom of the radiator on the side facing the firewall, somewhere in the middle. Unplug this while the ignition is "ON" and the fan should come on. If it does, the switch is bad. If the fans do not come on then the relay is bad or the fuse is blown.

Most likely the switch is bad.

thanks for the info...i will try that asap and let you know how it goes
thanks a lot for the help

Be careful to avoid the fan when you are unplugging the connector...

I had a 94 camry it did the same thing. It turned out to be bad wire to either spark plugs or distributor. I cant remember exactly now, it has been many yrs.