There is a video of a cybertruck driving through around 1m of water in wade mode: https://www.youtube.com/watch?v=4lKAEHMvvxg
Cheap plastic panels fall off in two places seemingly without any impact, exposing the whole underbelly and electrical system in the rear to water. The body retains water hours later and the buttons to open the trunk no longer work with them progressively failing in the hours since.
"Overall guys, things do seem to be... fairly normal. I do hear some water sloshing around in there. I'm guessing it will, kind of, you know, get out of where it's at. Overall the front was pretty dry. The trunk was pretty dry."
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