Originally Posted by pizzaguy

It COULD be the module, but I have a problem believing that. The control module essentially has two main sections in it.

1) A microprocessor based "brain" that takes the pulses from the ECM and sends acknowledgment pulses back to the ECM. This is certainly a Large Scale Integration electronic assembly that simply could not sink 50 amps without certain damage. I just can't see it sinking that current.

2) A switching transistor arrangement driven by the section above that turns the fan on and off. (At times it wants to run the fan slowly, it turns the fan on for, say 50 milliseconds then off for, oh, say, 250 milliseconds and repeats this sequence over and over).

I suppose the switching transistor(s) COULD become leaky, it happens in electronic police sirens all the time.

TO test it:

Start with a cold engine. (You don't want to hurt the engine by playing around with this while the engine NEEDS cooling.) Put in a new fuse. Unplug the fan from the harness. Turn the A/C on (so the fan is commanded to run at slow speed) and start the engine. The module will light the low coolant light because it senses there is no current going to the fan - don't let that bother you.

Give it several minutes and see if the fuse blows. If it DOES blow, the module did it!

If not, plug in the fan.
IF the fuse NOW blows, the motor almost certainly has to be bad.

If it STILL won't blow again....................................... welcome to the world of electronic troubleshooting.

ONE LAST THING: I have GOT to get some stuff done around the house, so I can't take time now... but there IS a possibility that the fuse feeds other stuff in the car and THAT is what is blowing the fuse. Again, it takes time to go thru the diagrams in the service manual, can't do that right now. Maybe someone else here knows...