Phaser 780 toner smear/lines on both sides of paper

[diamonddpgh]

Hello

Can anyone give me an idea what my problem might be?

I bought a used Phaser 780 that seems to be in good shape except that there appears to be horizontal lines/smears/streaks of toner appearing on the upper 1/3 on both sides of the paper even though I'm printing on only one side of the page.

I printed out the Service Prints 1 and the horizontal lines/streaks shows up on all colors. In the User's Manual they say that if there are vertical lines/streaks that could be a problem with the imaging unit, but these are horizontal, not vertical streaks.

There are no other printing quality issues like dark spots, white spots, white horizontal lines, oily streaks, discoloration.

I tried printing out the fuser cleaning pages and they come out clean, and the fuser roller looks clean, but when I print out anything with toner, I get the streaks. The more coverage on the page, the more toner streaks. If I have a lot of coverage, I'll even get a blob of toner on the backside of the page.

TIA!

David

 

[Michael52x]

If the image unit is okay, check the fuser roll.
Toner carousel may have a lot of toner built up in it.
Empty the waste toner bin.

 

[diamonddpgh]

Thanks

The image unit looks OK,
the fuser roll looks OK,
Not a lot of toner in the carousel (but I cleaned it out),
and I replaced the waste toner cartridge.

It still has the problem.