Hi all, I would appreciate some help updating my sat nav from V7 to a later version. It is a late 2007 E320. I've only just got the car and I've never had a Mercedes before, so this is all new to me. It is the comand head unit with single cd slot at the top, a 6 cd changer directly underneath the head unit and the sat nav dvd drive in the boot. The dvd in the boot is v7 2007. I have read I need to update to V12 first as this has a firmware update in it, is this correct? Does the update apply to the Sat Nav only or does it update the headunit? Do I just put it in the DVD drive in the boot and it automatically updates? If I update to V12 and the head unit is on older firmware, what will happen? Can I just put the V7 disk back in and all will work again? I am worried I will break something. I've read I need to potentially update the head unit before updating the sat nav using the download from this link: https://service-parts.mercedes-benz....&market=Europe Is this the same update as contained in the V12 disk? So this is where I feel a little lost, I've tried to access the engineer menu to get the version information using two methods, both with the car key in and turned on, but not engine running. 1. Going into service settings and language and pressing the two left upper and left lower diagonal buttons, the telephone cancel button and the audio button, that didn't work. 2. Holding the Serv button, phone down button and mute button. I have looked at th maps screen and I do have the eastimated arrival time, if that helps identify firmware versions. Any help or guidance would be appreciated. Thanks Rob.