Dim display

We have a WHIRLPOOL GBD307PRS01 30" BUILT-IN ELECTRIC DOUBLE OVEN CONVECTION-UPPER SELF-CLEAN (GOLD LINE) that is having display issues. The oven works fine as does the touch panel. The display almost overnight became very dim to the point of unreadable in some light conditions. Any suggestions on which part it might be. I was thinking of one of the following parts: [AP4909214](http://forum.appliancepartspros.com/part_details.aspx?part_id=3598617"]AP3598617[/URL] or [URL="http://forum.appliancepartspros.com/part_details.aspx?part_id=4909214). As there is a significant price diffrence I would appreciate any help. Thank you.