after replacing the thermostat with a low temp ( 180 degree ), replacing the fan switch with a 180 degree one, the fan still kicks on at around 240 degrees. It will shut off at 220. if the fan switch is a 180, shouldnt it send a signal to the ecm to turn on the fan at 180? this just doesnt make any sense!

 

When you have the system that has the coolant fan switch then it does not go through the ECM. It just supplies a ground to the relay when the temp is reached. Try unplugging the switch and grounding the wire and see if the fan turns on just for ****s and grins. If it turns on then the rest of your system is working proper and maybe its possible that your switch is not a 180.

 

i just grounded the relay (dont remember which wire) to a switch so i coujld turn it on/off as i wanted

 

i'm just confused. i just replaced the coolant temp. sensor and it still went to 245 before the fan kicked on. I turn on the a/c and it still doesnt come on ( fan )
so, how can i hook up my own switch to turn it on? I'm not too good with electrical stuff

 

Where was this fan switch you replaced? What coloer were the wires? And to help out a little more what year and the 8th digit of your vin?
When the a/c swicth is turned on it supplies a ground to the relay through a [usualy] green and white wire.That wire is the same wire that gets its ground from the temp swicth. You can go to that wire at the realy and test it for a ground when thea/c is swicthed on and if none then test the switch itself.
But if your not good at electrical then we can explaing this until we are all blue in the face(or fingers)in which case tell me the year and vin and I can scan and email you awire diagram and you can look at it yourself.