i had the gap between the engine buikheads where the battery sits fill up with water and freeze so dead battery on replacing i noticed a clear tube in a black coragated outer laying behind the battery where does the end of the tube go and what does it do as at present it apears to come off a connection somewhere since the flood the centrall locking is not working and the central dash display characters apear broken up the car is a a4 2000 w reg

ihope someone can help a the car deserves saving regards mrplastic