7 Pin Connector corrosion issue

I do leave it open to the air. the pinbox is completely open at the rear and cord just lays in the open hole. I have used a nylon mesh over the opening at times to prevent birds from nesting in the pinbox, but that doesn't affect airflow.

I'll try a little contact cleaner to help remove any oxidation and then seal it with plastic wrap airtight to see it that solves the problem.

Thanks for the answers.