I am having trouble diagnosing the cause of a one inch lined blotch which starts two inches from the top of the page and runs full bleed from edge to edge across the page. It is usually worse with graphic intensive print jobs.
If you print two copies of a page in the same print job, the second page comes out almost clean.
This started when the toner cartridge was last changed. I attempted all the various fixes including cleaning everything including the LED print head without success. I then tried replacing the toner with another new one because it might have been old toner. It continued to print blotched output.
The blotch is not caused by a misaligned wire cleaner.