Have a 94 325is. Original changer went dead. Got a 96+ head unit, accompanying 96+ changer cable, Soundgate AUX adapter for XM. Put in the head unit, works fine. Put in the new changer cable tonight, put in the soungate, everything hooks up fine. The original change power plug is a two wire, the soundgate unit expected a small 3 wire plug, apparently what the 96+ uses. Found a pinout, #1 is ground, #2 power, #3 ibus. #1 and 2 no problem, found a small connector and spliced it in, but have nothing to hook to #3. Turn on the radio, let it play and hit CD/TApe, all i get is "no tape". Doesn't see the SG. SG unit has power and ground and a live audio source. Is there something to do to tell the head unit it's here??? HELP!!