HP LaserJet 4MP faded print

[dferreyra]

MichaelTech, thanks for the suggestion. I'll give it a try when I get the chance, though I don't know how successful I'll be. From what I remember from the service manual, getting to the high voltage assembly was a lot more disassembly than I've attempted so far.

Dean

[RogerF]

Remove the high voltage assy, under the printer and clean the contacts wires on the board. They look like staples, use a brush.

I have the same problem as the OP: very faded prints. No error codes on self test. Halfway test shows almost no toner on the drum. I followed your advice to clean the HV contact wires but it didn't solve the problem. If the laser were weak, would I expect to see an error code? Or is it time to replace the DC controller board assuming the HV is failing?

Thanks!

[woodss]

Just a quick update, I've given up on the 4MP and I've bought a refurbished HP LaserJet 4000TN from PrinterTechs.com.

I bought the 4MP new in 1994 and it's done well until now. Now I just have to figure out what to do with it.

Might be good idea to retire the old thing but sometimes dust can get inside the laser scanner usually a blow with compressed air can fix these problems, but 4MP are very slow, 4ppm, the 4000TN is a much better unit.

I personally use a 4300DTNS, which has duplexer, and 3 500 sheet bins and a stacker tray, this unit was made in October 2003.

Used since 1994, thats nearly 20 years so it has done its job really well, my junk internet printing printer is the HP LJ II Its now 23 years old, Jan 1988, and just had its regular annual yearly service, every year on the month it was made the printers I have a annual service mainly cleaning the inside and inspection of major parts. such as rollers and the fuser.

When I see these problems, I check the laser scanner for dust and transfer roller.