What would cause this on my HP 4M+? See pic.

[rotaryboy]

Printer otherwise works well except for a few jams. This was a freebie so I can order parts if necessary.

Thanks
Brad

[MichaelTech]

Looks like your transfer roller is either dirty, or the H/V assy is bad.
Try another toner? Pull tray out, tip unit up, black rectangle is the H/V/. Two screws, and squeeze top and bottom to pull out. RG5-0513
Could just need blowing toner out of H/V. Check the toner contacts also.

[woodss]

I think its the printer having its scanner mirror dirty, dirty transfer roller as michael said, and try the suggestions that michael said too.

take the printer apart and give it a decent clean that would help.

Hint: Take out toner cartridge and open the bottom lid and check the toner cartridge, execute a print job and while its printing approx 2 secs later open the lid.

Look at the print out before it comes to the fuser and then check the drum on the cartridge see if it has the same problem if it has then its the toner if its not then its a dirty transfer roller.

If its not that then I would look at cleaning the contacts and cleaning with compressed air on the H/V Power supply.

[rotaryboy]

Well I tried all the above suggestions to no avail. Surprisingly the scanner/mirror and related contents were clean. Transfer roller a little dirty but cleaning did not help. What did help was a new (original 92298A) toner cartridge at $100...OUCH! I now cannot believe the speed and quality of this 13 year old dinosaur....NICE! Thanks for all the tips though it was interesting field-stripping my first laser printer.

[Brian]

I don't know how somebody can suggest that black marks on the print out can be caused by dirty optics.
If you have dirty optics part of the image is lost, it doesn't add anything to it.
If you look at the old cartridge you'll see the drum is worn.