This Citroen DS3 came to us with wet carpets on the front. We were eventually able to track down the problem to water leaking through the bulkhead via the air-conditioning unit.
Unfortunately, this is not something we can fix, it will need to go back to a dealership for them to remove this and replace the seals. We have found out that this problem isn't unique to this vehicle and can be an issue on Citroens.
This video illustrates the kind of corrosion you can get inside a car which has a leak. You can see there is rust on bare metal which hasn't been waterproofed because it was never supposed to get wet. Similar corrosion can and will appear on electrical connections as condensation will settle on any cold hard surface. Over time this can lead to electrical problems which can be expensive to remedy.
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