I was wondering for what reason I get water condensation on the glass cover inside of the 4 small middle instruments (water temperature, oil pressure,...) when light is switched on. Seems that there is water in those instruments which warms up by the light bulb and is then condensing inside on the glass cover. Since many years my car has not seen any rain. Even in hot and dry summer I see the same effect in the instruments. I would expect that any water, by whatever way it entered, would have been entirely evaporated after a hot summer. The carpets are dry and I have not noticed any leakage of the heating system.
Do you have any clue?