Hi, so I've had a '99 528i, lost it, but the nav OS wasn't with the latest OS, I got it back in '07... anyways, I have a '04 E53 with MKIV I assume, my nav system reads 4-1/20... or something like that, and from prior posts I have a VERY old OS...brought the SAV in Jan of 2013 from a private seller who never used the navi because he said it drained his battery

.. I felt however that it was perhaps his screen and not the system so I swapped his ink blemished screen out with my unblemished screen. Suposedly when he had it plugged it would drain the battery "within a few days".
My whole point of my post is if I should update the navOS, and I do want the custom splash screen... there are too many pages to read to follow this discussion and if I should update do I use a blank CD or DVD? Where do I get the new maps from? the one in my nav currently is a 2002 map.
Thank ANYONE for some insight