LaserJet 1012 Vertical Fade

There are 3 possible causes of a shadow.

1. Toner cartridge, which you've eliminated.
2. Crud in the fuser assembly. This the most common.
3. Dust or dirt inside the laser scanner assembly. This can usually be cleaned out with compressed air. Note that an obstruction to the laser beam will create a vertical black band, not a faded band.

It's not the laser scanner.

Before you tear into the laser scanner assembly, check if there's a corresponding 1/4" wide band on the fuser assembly. I'm fairly sure that's where you'll find the problem, in the area of your "slight fading". If you disassemble the fuser assembly, you'll probably find a thermal sensor touching the drum in the exact area of the problem. I don't recall exactly what it looks like in the 1012, but it usually has a yellow mylar tape cover. This tends to collect toner, which melts in place on the thermal sensor. That will eventually wear off the coating from the drum, resulting in a faded area on the page, exactly what you're getting. The clue is the 1/4" wide band. That's the exact diameter of the sensor. Scrape off the melted toner from the surface of the sensor, and it should work.

Light reading:

I concur with Jeff, but would also suggest removing the toner cartridge and shaking it smartly to make sure the toner is evenly spread inside the cartridge and not missing from one side due to the packaging during shipping..

Bob

I did try the shaking to no avail. Before following the fuser trail, I removed the cartridge, depressed the laser shutter lever, and inspected the laser lens area with a dental mirror. I could not see anything on the glass, but used a blast of air. Faded vertical stripe almost invisible now. [I probably would not detect it had it not been noticable before.] So I will stop while I am ahead. Thank you for your assistance.

Their is also a transfer or corona wire that gets crud on it, but its usually the fuser.

I can't comment on that particular unit, but I've always cleaned laser optics by simply removing the cartridge & dusting out the slot in the laser module with a large, soft brush. On some models, there's a hinged flap that needs to be moved to expose the mirror/lens.

Assuming that your cartridge is perfect, another cause of vertical, faded stripes is a dirty corona wire or roller.

Woops! Good point, Jeff, I was forgetting that lasers "write white", not black. Dirt on the lens/mirror gives you shadows, not fades.

No, you're right.

Another typical symptom of a stripped fuser roller is that the toner also doesn't adhere properly to the paper in that area. Scratching the print in that area with your fingernail will often lift toner.

If the teflon coating has been scraped off the roller in that area, the roller will need to be replaced. Replacing the roller itself is a tricky job on most lasers. It might be possible to replace the whole fuser assembly with a refurbished unit.