E34 code on the radio?

Every time when the engine is started there is this "E34" code displays on the stereo. It stays there for like 10 seconds and the display returns to normal. Everything seems work as usual even during the code is being displayed. The car is a 2000 GLS Sterling Edition with Bose stereo. I wonder anyone out there ever experienced this and what the deal would be. Thanks!

Never mind. It was the CD changer in the trunk somehow having its door open that was giving that code.