OK I got the mystery solved. This is good info for those with 2004 who are putting in GPS which is an '05 option. It appears as they went from in '04 a miniature Mercedes plug to a BMW larger plug for the am/fm radio. You can buy an adaptor at circuit city that goes from BMW large plug to standard RCA jack and another cable from RCA to miniature. Costs about $40.00. Once you have purchased this you then just plug the GPS into the small plug near the harness. Having done this now if anyone is doing this PM me and I'll gladly help. If anyone wants pictures I can do that too. Thanks for everyone's efforts. Sorry I was a little short but I was up late and it was baffling me.