I was told this was a multifunction sensor, but the part number is 211 830 04 72. Mine is faulty and I require a new one, I was searching online to buy a new one and some have "Q04" on it (mine does) and some have completely different numbers like Q03 and Q01 and Q13 etc... Does anyone know the difference between these or are they the same and it doesn't matter which one I buy? Thanks.