VW SD Card Navi Discover Media Gen.1
Hi folks,
I just want to share my experience on VW Navigation SD card,maybe someone make use of it. Not about media, but about original VW Navigation card.
Got a used Golf mk7 with Discover Media Gen1.
It had the obsolete 2014 SD map card that came with it, wanted to update.
So I downloaded the Discovercare VW program, had a spare kinstone SD to try. Quickly learned that a 3rd party SD won't work with this head unit, as it uses a VW custom SD card with special/hidden sectors in it. Or ID..?
So I made a backup with Win32diskImager of the VW card, then let the Discovercare upgrade it. Finished OK, but the head unit didn't recognise it.
Did it again with other maps. Same result. So I wrote back the original backed up image. Head unit did not recognise! Then I made a file compare of the card and the backed up data made by Disovercare and realized that the files had different content.
Double Commander, and Total Commander had a "synchronize dirs" function that is excellent for comparing directories.
Then I made a file content comparison of one differing files. Realized that the card hex values were always higher ("7" the value, "F" on card)
Checked it also on Hex editor (WinHEX). Thought that the SD card maybe got faulty that some bits stuck on "1".
I tried to zero out the whole card with DiskWipe that writes zeroes until it reads back zeroes. Damn slow. But I checked in WinHEX that yes, the bits really got 0. Then I wrote back the original image with Win32DiskImager.
It worked, but I was back to square one.
Wiped again but that was discovercare did not recognise it. So I unzipped the map and copied the card. Head unit did not recognise it. put it back to laptop and realized that the files had differences to the ones I copied from the HDD. Then I realized that damn windows created System Volume blabla, and one other system file, and whatever change I make to the card makes changes to the file system actually corrupts the card. Writing is OK but modifying is not. Found out from WinHEX.
Then I made wipe again (1.5hours for a 8G card), and without writing anything to it I plugged in into my old linux laptop and copied the files in one sitting. Compared the files looked OK, and works OK on the head unit also. Although it needed a complete reboot of the unit till it could show the map.
So DiskWipe.exe > copy map files under linux in one sitting.
Immediately unplugged and locked.
Not sure after all if it worth the effort I put into this, as it took me like 6 hours to make it work, I just looked it as a challenge.
Also I'm not sure if it is card ageing problem, or what.
I see others selling this cards for like 20-50 $€Ł, but I thought if it is not new might have the same problem sooner or later.