My cx11nf printer is printer lines on the long sides of the printouts. ie, it appears to have 2 lines of substantially less tone on both the 11" sides of the printouts. Wondering whether this would be a photoconductor problem, toner problem, head problem, ...?
This could be caused by a dirty lens on the laser unit. Try cleaning the laser window. Open the front panel (where you change the toner) and the right you will see a blue lever/handle - pull it out towards you. Now on the right side panel of the printer you will notice a little plastic panel about 2"x0.75" - open that and you will see inside another handle. Pull this handle out and back in a few times. This draws a cleaner pad across the lens. If toner has fallen onto the lens it makes the are it has fallen onto create blank lines on the print. If this does not solve your issue then the next suspect would be the PCU. Just get another one (same as C1100 if you can borrow one) and try it.
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