Drove through some mud yesterday and after cleaning truck I noticed a plug hanging from bottom of radiator (engine side at bottom on passenger side of vehicle). Mud had pushed the plug off its retainer clip. I put it back in the clip but the plug is open-ended and is female ended with 8 openings. Cannot find anything under the truck that looks like it should plug into it. Also, should there be a protective cap of some sort to cover the prong holes if it is supposed to be a dead end?
By the way this is my first post--GREAT site!!! I have learned a lot about the '04's just by reading the forums.

 

From the brief description you provided I think you are describing the fog light connector. If so, you must not have the optional light package. Clean it up, put dielectric grease in the connectors, and tape it to keep it clean.