96 tracker check engine light fraud?

[redrube]

I recently bought an old 96 tracker, and I just discovered that the engine computer is throwing some codes, but the check engine light isn't on.

I look under the dash, and I see this plug just hanging out, not connected to anything, with some odd butt-connector splices behind it.

What is this plug? I have been digging through the Haynes manual for some time with no luck.

And can anybody tell what the purpose of these two splices might be?