Go (and this is the hard part) READ this article:
About half way down there's a section called "Resolutions:" where it mentions some LEDs are lit dimly. Note the item dated 20-Jun-08 and the photo.
Remove each of the filter/pin assemblies (two Torx screws) and measure each pin to the connector ground. You should get over 20 megohms on every pin. Scrape the crud off the ones that don't until they do. Check and clean both sides. Do each filter/pin assembly separately and remember how they go back in as there is a top and bottom, left and right. Use a permanent marker to make a mark in one corner of both the filter/pin assembly and the chassis.
Bob M.