Hmmm.. .I see the problem looks to be something to do with the coolant temperature signal actuating the relay.. That is done with the PCM.
So I would say.. since you know the sensor is good.... Make sure the right signal is getting to the computer. Here is the resistances:
.. and here is the diagram mof the switch, so you can see which pins the wires go to on the PCM:
OK.. for the computer to turn on the relay, it needs to have a signal saying that the engine is up to 220 degrees.. And it turns it off at 210 degrees.. or so..
Once you get the desired resistance at those terminals , yuou should have power shoot out to the relay.. Here is a pdf of which pin that is on the computer...http://senduit.com/ff8f53
If you dnon't get a signal there.. well, the circuit in the computer looks to be fried.
If there is power there, then there is a break in the wiring between there and the relay. I can tell you that sometimes the terminals push out of the relay sockets.. and even when they crimp the connector to the wire... it wears into and actually breaks the wire causing a bad connection that is very hard to find!
If you still don't find the problem, then it will have to go to a shop to be hooked to a scantool that can communicate with the computer and activate systems for testing, etc... This is a very expensive piece of diagnostic equipment, not just a code reader...and only a qualified professional will have access to one.
Hope it helps.