I'm not aware of any special code that is needed on mine. My battery has been out of vehicle for several hours, dead on several occasions while waiting on parts to come in and disconnected several times for window regulator failures and never any code needed. It even keeps my radio stations programmed. I can't tell what station it is looking through all the dead pixels but I recognize the DJ's voice.

__________________
2010 Lexus RX350 still new
2003 BMW X5 3.0i w/sport package w/68K miles. (gone Thank God!)
2002 Dodge Ram 2500 4X4 cummins diesel w/198K miles, custom repo truck
2009 Scion tC w/46K miles
2007 Suzuki SV650 custom streetfighter
2000 Lexus GS400 w/165K miles