[dataway]

I was under my 2011 Sierra doing some pre-winter oiling and I noticed what appears to be maybe some kind of control module located above the driveshaft, between the mufflers, not far behind the transmission. Couldn't see it very well, it was covered by some kind of metal cover which is in the process of rusting away. I could see a fairly large bunch of connectors plugging into it.

Underside of the truck is in very nice shape except this cover, so I was thinking I might try to replace it ... problem is I don't know what it is, or what it covers so I can't look it up. Doesn't show up on the parts diagram for bed or frame.

Is it a control module of some kind, or just a harness junction?

Thanks