the 2nd picture is after sanding,seems to be moistly surface rust..checked my drain holes,one was blocked.View attachment 145500 View attachment 145500 View attachment 145500 its inside the speaker panel at the bottom ,found out there are 2 drain holes on the leftt ,seems condensation ,builds up on the inside of the other panel,drips down, Renaults answers to this was to put 2 holes at the bottom..ha
you need a mirror or a camera to see it
I would check yours if I was you, I have put silent coat and foam insulator in the passenger side panel, put everything back. i will have to take it off again.get a camera down, to see its the same as the drivers side. it seems 10 years of condensation, can do a lot of damage.the 2nd picture is after sanding,seems to be moistly surface rust..checked my drain holes,one was blocked.
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