Just bought a 2010 TL SH AWD (and love it!). The previous owner had a PIN on his home address in the nav system that could not be wiped without a service call. Using the standard menus to wipe personal info, address books, etc. wouldn't touch it. The dealer contacted the previous owner who offered up two sets of numbers but they didn't work (nor did the "usual" ones). So I took it in for a service call. On the good side, the dealer installed the latest map update for free and was able to wipe out the PIN. On the not so good side, not only were all my previous addresses erased (expected), but so was my phone information (pairing, speed dials, address book, etc.), AM/FM pre-sets (XM ones remained), and all of the music I had ripped to the HDD. I didn't expect that much of a wipe - easily replaced though. Just posting mostly as an FYI for anyone who may go through this in the future.