Question about my ECT switch and my rad fan.
 

So my Radiator fan is not working...still...I narrowed it down to the switch since the fan works when i hook it up just to the battery and replaced the switch thats on the back of the block by the oil filter but still no luck...
I was just wondering what else it could be. maybe the wiring from the switch? Theres a yellow/green one (goes to the fan) and a black one (ground)...does it matter which prong i hook it up to or will either one do? I tried to hook it up the way it was before but i don't know if its right or not.

My car doesn't have AC so there is no relay according to the schematic so its just the ECT switch that turns it on....i can't think of whats wrong here!!
....any help would be appreciated.

Here's a clip of the schematic.

http://img175.imageshack.us/img175/2615/untitleder6.jpg

well check for continutity (sp?) in the circuit or in other words.. opens. I assume you checked the basics (fuses, corroded connections, etc). If you replaced that switch and the fan works when you hook power up to it, it must be faulty wiring. either an open or no ground. When your car is above 90 C check for power going to the switch and power exiting the switch.

So the way i wired the prongs wouldn't have a difference though?

I'm assuming there's a problem with the wiring itself too just making sure i hooked up the switch the correct way first...

If it is the wiring thats going to the fan thats bad, what do i have to do? Is this a big job to tackle? do i just run new wires to the fan and a ground or is there anything going to the ECU that i have to rewire? Is this the sensor that the ECU is using to change the A/F ratio for cold starts too or is that located somewhere else?

Sorry for all the questions.

just check if the switch is getting power and ground at 90 C.

Yes, the ecu does use the ECT to change the afr's as well as a few other things.

what car/motor/obd are we talking about?

you might be mixing sensors/switches up
theres a coolant fan switch its an on/off temp switch turns the fan on and off
a coolant temp sensor its a thermistor, gonna have a variable output for the ecu
and a temp sending unit for you cluster

short out the connector to the fan switch and turn key on engine off to see if your fan switch is inop