Elec Fan stopped working

Had an overheating problem. At that time my elec fan was functioning as designed. Replaced Thermostat and that fixed overheating issue.
This weekend I discovered the elec fan was not coming on when AC turned on. Replaced relay... not a fix.
Googled and found a printout from FSM. So shorted pin 2 & 4 at relay like their drawing said. Fan powered on as designed. Checked other relay point for 12vdc and was there as designed.

Moved to the temp switch test on thermostat. Supposed to unhook plug and short two pins on connector if fan comes on (IT DOES) than replace temp sensor.

Replaced Temp sensor and still does not come on

Next it says the temp fan diode needs replacement.

I googled further and I don't think my 2000 4L has one? Does anyone know or have suggestions what I can check>

I know I could just add a switch for fan but would rather not.

The 2000-01 e-fan only turns on when called for by the ECM. With the older models the e-fan cycles on-off continuously when the A/C, or the defrost, are on.

With the engine running, if you (carefully) unplug the wires from the fan temp sensor on the thermostat housing, the e-fan should start up. If it does, everything is OK.

What is the "it" you are referring to, some kind of service manual ?

I've had a similar issue where the fan fuse leads got to where they wouldn't make contact. Fan would start sometimes, not others until it didn't start at all.

Give it a look. It would show continuity until load was applied which made trouble shooting a pain. I basically jumpered out the relay, wiggled the fuse, and got a fan start. Ended up having to wire a new fuse holder around the old spot in the box as it was too burned up to work consistently.

Tim_Mn that makes sense! I will let it idle in the shop for temps to rise and see if it cuts on