Does anyone know how to access the navi service menu? On the 3G you held a bunch of buttons and it would open.

 

If I remember right it's holding the menu, cancel & map/guide buttons. It's been a while since I tried it though.

 

Thanks that worked. I had a few messages in the navi that could not be deleted through the regular menus from before I got the car.

 

Sorry for the thread necro, but the buttons are different for the 2012-2014 head unit. From the 2012 model service manual:

Start the vehicle, and at the disclaimer screen use the navigation display hard buttons:
Press and hold the DEST/ROUTE, the MAP/GUIDE, and the CANCEL buttons for about 3 seconds. The
display screen goes directly to the Select Diagnosis Items menu shown.

Hope this saves anyone else after this info some time!