What is this plastic piece?

[Groovy]

I don't leave the truck outside at our house much. My wife noticed a squirrel jumping up into the engine bay (from below.) I used the key fob to honk the horn and scared him out, but noticed this on the ground in front of it. Is it part of my truck or just happened to be there? It does have a part number on it but Google doesn't reveal anything. 7174-1729 CAV5.View attachment 156473

I just found this exact cover in the engine bay of my new RAM. I searched the part number on it and this thread popped up. I figured it was a cover for a electrical connection port removed during assembly but wanted to make sure this wasn't something that popped off and should be in place. Based on the responses to this thread, I guess it a cover for a port that is removed when engine is installed and electrical connections made.