Hey all, not sure if im doing something wrong, just went into my merc and changed the settings from kph to mph but still showing kph, this is what i did, turn the keep to the 2nd position then went though the menus and change it to mph then i pressed on the button with the 2 windows assuming that it will change to mph but it still showing kph, took the key out and back on and still the same, do i need to start the engine to change it?