I noticed this on my new to me 2015 Trailhawk a couple of days ago. I also noticed a bit of mold/mildew right under the edge of the deck lid. I'll update with pics shortly.
Appreciated. There's no standing water. I've had no problems with modules but I'll check to be sure. Put a fan to it as needed then clear exterior silicone and call it a day.Take the floor out of the trunk, remove the water and dry it out.
Check all of the modules (computers) for corrosion. Check the connectors. Clean as necessary.
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