jthemuss

Just recently installed a Sony DVD head unit to my 2002 lexus is300. After professional installation the OEM sat nav wouldnt work. The car audio place advised me that it was due to the new head unit installation, but i have seen other IS200/300's sat nav work even with new headunits installed and even working together. Has anybody experienced this issue before, could it be connection/ wiring problems or is it possible just to replace the OEM sat nav with a new one? Jay