Hi i am having trouble figiring out why my coolant fan wont come on. The car recently started over heating randomly once a few months ago then again a month ago and then a week or two ago. It only overheated when i would be idling for awhile like in a long drive thru or heavy traffic. So i decided to check thermostat which i replaced and it seemed like everything was good till yesterday and it didn't over heat bur was heading that way its such a slow climb up that i knew it wasnt the radiator or water pump so i got it home and its the fans they arent coming on at all and i cant figure out why. So how dovu know if rhe moror is bad or the relays what should my next step be. I have check all the fuses insise and underthe hood and fuse able link outside the engine compartment fuse box all good

 

Something you might consider,

If we disconnect the fan motor from the system and supply power directly to the motor , it should run. If it does, the motor is usually OK.
Next we need to either use a wiring diagram or trace the circuit to see which relay energizes the fan motor. With the cooling fan reconnected, we can verify if the relay and wiring are sending power to the fan motor. Once we know where we stand there, then we check to see if the sensor/switch is working correctly and sending the signal to the relay to energize the fan motor..
Somewhere ,there is an intermittent connection, wiring, or signal causing the fan motor not to come on when request for operation is called for.
If you do not have the equipment, info or tools to carry out this sequence, best to have a good shop check it out.