1. An vehicle diagnostic tool, comprising: a data link connector that receives data from an onboard vehicle computer; a processor linked to said data link connector wherein said processor executes a diagnostic application program on said data received at said data link connector; and a display linked to said processor wherein said output diagnostic data generated by said processor running said diagnostic application program is graphically displayed; wherein said diagnostic application program can generate a non-zoomed-in region and a zoomed-in region for a selected item of output diagnostic data, said zoomed-in region having graphical coordinates on one axis greater than the graphical coordinates of the non-zoomed-in region on the same axis.