Suspect the relay. Instead of the extremely reliable part it used to be, it's a computer module now to provide variable fan speeds to address the whiny complaints that people could actually hear the fans run. As all computers, it gives lots of trouble, and is a common failure item.
The relay lives about halfway down along the driver's side of the radiator. It has four wires and is bolted to the core support. When you mount the replacement, be sure the metal surface is clean and the relay is bolted solidly for good heat transfer. If it is not bolted to sheet metal, it can get hot enough to burn your hand.
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Thursday, August 25th, 2011 AT 8:00 AM