hello I have a problem with a mercedes sportcoupe car ? affixed to part quietly it gives me no error with autocom the problem that if I leave it stops 7/8 hours I find myself with the battery completely to the ground,I restaurant the battery with a new one the same amperage,I have disconnected both radio and any other thing possible in practice now ? as if it would be the original alternator charging then not ? a problem of charging ,if I detach the battery and I leave it stops the day after in the riattaccarla part safely can you give me some advice?