HP 2600n: Faded Prints and Laser Scanner Contamination

It is typical to attribute the faded or worn out printouts produced by color laser printers to a low or depleted toner supply. Now this can be easily resolved by replacing the toner cartridge or by replenishing the toner supply of the exhausted cartridge with compatible toner supplied by an HP toner refill kit. If upon ocular inspection, the cartridge still has sufficient toner and the magenta cartridge is likely causing the fading prints, then this could be a case of "laser scanner contamination."

This condition can easily be detected in the HP 2600n color laser printer because of its design alignment where toner cartridges are stacked one above the other. However, this is not a design flaw of the print engine. The magenta cartridge is positioned on the bottom part of the array and therefore has the tendency to absorb loose toner and dust the most; to contaminate the laser scanning assembly eventually.

http://www.flickr.com/photos/oskay/ / CC BY 2.0

The print engine of the HP 2600n color laser printer comes designed not only with 4 toner cartridges but also with 4 OPC drums, 4 laser scanning assemblies; one each for the Cyan, Magenta, Yellow and Black toner cartridges. It is only unfortunate that the design calls for the magenta cartridge at the tail end of the cartridge array.

Over time, loose toner powder and dust collects on magenta cartridge components coating the sensitive laser and rotating reflective mirrors or lenses which consequently reduces its capability to accurately emit required light pulses on the OPC drum to form the latent image.

Failure of the laser scanning assembly results in faded or worn out color prints. Maintenance of the laser scanning assembly does not form part of the HP 2600n printer's internal cleaning features. Therefore, only manual troubleshooting will do the trick. The task of cleaning the laser scanning reflective mirror and lens is a simple matter, particularly with the printer service manual around. However, the location of this component inside the printer could not be easily reached and in fact entails dismantling the printer. For the beginner, that would take a couple of hours to complete the job.

The task is therefore best left to printer technicians to do justice on the cleaning of the laser scanning assembly.

-----------------------------------------------------------------------------------------------

Are you using the

HP LaserJet P2035 series laser printer?

The unit's toner cartridge can be recycled

for another cycle of printing using a compatible toner refill kit.

Get the HP LaserJet P2035 High Yield Black Toner Refill Kit today !

Available from Laser Tek Services for only $26.95.

-----------------------------------------------------------------------------------------------
Kit refills the following HP cartridges: CE505A CE505X. Save up to 80% from the retail price of the OEM cartridges when you buy the 4 pack.

Using an HP toner cartridge from another printer series? Check out our HP compatible toner refill kits.

Troubleshooting Print Defects: When the Drum Unit is Suspect!

Troubleshooting print quality troubles for the HP LaserJet 2550 color laser printer based on a defective printout is a tough nut to crack. A laser printer is outfitted with several components; from mechanical rollers, to the photoreceptor drum, the toner cartridge and the fuser assembly. Each of these components is capable of inflicting toner smears on the printout. The only sure way to correct faulty prints is to pull out the suspect component responsible for pertinent print irregularities and physically check it for defects. However the process is tedious, because it involves ocular check-ups of selected, if not all components that come in contact with the paper (medium).

Measuring the Print Defect
Hewlett Packard however made troubleshooting for the HP 2550 so much easier with the use of a repetitive defect ruler. By measuring the actual dimension of the defect on paper (using a ruler), the ugly head of the suspect component can be identified. Since we are dealing with a defective OPC Drum, the repetitive defect measures 148.3 mm in length. Said measure actually indicates that such defect is produced by a defective photoreceptor drum. From thereon, the user simply needs to pull out the photoreceptor drum and physically assess its condition. If the defect is more pronounced, it has to be replaced and if defect is not visible, the drum probably just requires cleaning.

Replacing the Drum's Lockout Chip
Photoreceptor drums are designed with electronic based microchips or lockout chip that count the actual printed pages and consequently desist printing once the rating limit is breached. Standard capacity of the photoreceptor drum is from 6,000 to 8,000 copies at 5% coverage (the industry standard measure of page coverage) and the microchip nominally bars printing after the stated limit. However in cases where not a single defect manifests at the time printing stopped; it could only mean that the OPC Drum is still in fine form and the user will only have to change the lockout chip to commence printing.

Replacing the Drum Unit
On the other hand, if printouts have defects attributed to a defective OPC drum unit, a physical inspection of drum surfaces will not always be a sufficient indicator of the component's actual condition. A tear on its selenium coating is a visible defect (easily recognizable) but if the drum has lost its photosensitive properties, then no amount of physical inspection will be enough to determine what is really wrong with the component. In cases where the OPC drum is suspect and the defect persists, the only choice is to replace the OPC Drum.

Remember that while print defects are a regular fare for laser printers, most print quality troubles emanate from a toner low or toner empty, toner cartridge and seldom do these stem from faulty printer components. Defects attributed to toner empty cartridges can be resolved with the use of a compatible toner refill kit; where the supplied compatible toner powder is used to replenish the cartridge's toner supply. The bundled cost of OEM HP 2550 toner cartridges is around $350 with each cartridge having a capacity of 1,500 pages at 5% coverage. Read more about toner refill kits from our previous post.

For those operating on a shoestring budget, the compatible HP toner refill kit rainbow pack is retailed for less than $100 but delivers similar print performance and yield as the OEM toner.

Read a related post on How to determine if the laser printer drum needs to be replaced?