I have a 1999 E36 convertible with the OEM Business Radio cassette player and boot mounted C.D. changer. The front engine fans remained on a while ago completely flattening the battery. Thats all sorted now, but in the process the power was lost to the radio so it needs to have the code entered before it will work. In my case I have the original code card, the serial number matches on the card and the set, but the code does not work. I was under the impression that the codes in these sets were hard wired, i.e. the customer could not change them. It is likely that the set has never had the power removed before so would the code have been wrong from the outset? I have tried one of the coding services and they have been very helpful but were only able to tell me that the code they come up with is the code non functional code I have. Any one advise? Thanks in anticipation.