any one use the calibration function of the nav? my system seems to be slightly off and it looks like the cal function will allow you to adjust. my only concern is if i go too far off is there a way to go back to the factory settings? i would hate to find out i made it worse and then not get back to where it was (overall the system is fine, but in a resdiential area for example the system is 1-2 houses off, i would love to tune it in if possible)

 

The navigation disc does not have GPS coordinates for individuals homes and businesses. It just knows the range of numbers on the street, and the software assumes that they are equally spaced. Needless to say they aren't, which is why you'll see it off by a few houses. If the system is showing you crossing street intersections at the right time, your calibration is fine.