Clean the LED's.
1) In the Applications Menu on your copy screen there should be a option to turn on or off a background color fill. Turn it off and try. If it still comes out try hitting panel reset. If this doesnt work. 2) You have a bad Image Unit. Change the yellow image unit. 3) You may also have a bad write unit. Pull out the four write units and check the yellow write unit. It may have gone bad in which case it needs to be replaced.
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