When I print colour prints on my HP 2605DN the red ink is always missing although there is plenty of toner left. This problem started about a year ago and it got gradually worse. Now there is no red ink printing at all. Any solution for this?

This printer does not use ink cartridges. It is a laser printer and uses toner cartridges. Yes, one or all three toner color cartridges maybe running out of toner.

The 2600's and 2605's share the same problem.
The scanner has to be removed and cleaned because magenta toner builds up on the laser scanner mirror.
You need a service manual.

Hi your heads need cleaning may have to take out to clean

This is a common problem on these printers.

Cause is dirty lenses and or mirrors in the laser unit.

Solution is remove laser unit, open it, clean lenses and mirrors (very carefully to avoid disturbing alignments, and scratching).

The laser unit is deep in the printer, so it's quite a lot of work, but very rewarding when you've fixed it.

Alternatives - buy a replacement laser unit and swap and clean old one at leisure, or get an exchange refurb printer - if you think your mechanical skills arn't up to it.

Here is my solution, hope it will solve your problem.

From your post, I believe your CLP-350N printer has enough black toner. The black cartridge is on the far right side of the printer, so the black toner is harder to go to left side of the roller than right side. Everytime we start the printer, it will move some toner of each color to the roller before it shows ready to print.

Because we always use B&W printing when we start the printer, but less Color printing. The result is there are always enough toner on the 3 color rollers, but the black toner is lean on the black roller. When this gets worse, the left side of the black roller may hardly get any toner at all -- so it only print black on the right side fo paper.

Step by step solution
(CAUTION: Never loss balance while tilting printer! You may drop and damage your printer! Hold the printer firmly all the time! Ask someone to help you if needed!)

Here, front of the printer is where you can access the cartridge, back of the printer is where you connect the power cord and USB cable, left is your left, right is your right.

1.Lift the front to keep the printer tilt to its back at about 45 degree
2.Power on printer while it's tilted back, wait untill green light is on
3.Open the front door, red light will be on, then close the door, printer will start up again,wait untill green light is on
4.Repeat step 3 once again, then put the printer back to level position
5.Lift the right to keep the printer tilt to its left at about 45 degree
6.Open the front door, red light will be on, then close the door, printer will start up again, wait untill green light is on
7.Repeat step 6 once again, then put the printer back to level position
8.Print some test page to see if there is any improvement of black print quality.(Hold the printer button for 3-5 seconds, it will print the test page.)

You may try several times and print several pages each time before you finally cure the problem.

Good luck! And do it safely!

Probably a dirty laser unit.

It's cleanable (but you need to take care

1 not to scratch any of the surface silvered mirrors.

2 not to disturb the alignment of any of the optical components.

It's quite a bit of dismantling (you start from the back of the printer and work your way 'into' it until you get to the laser unit). Youcan then remove the laser unit, open it up and clean it.

The printer head may need to be cleaned. You can buy a cleaning kit for the head.

I think this will fix your problem. http://www.reeves-hall.net/tech-gadgets/fixing-washed-out-colour-on-hp-color-laserjet-2605/

My HP2605dn does this about every 6 months. I am getting fast at fixing it. The laser mirror for the red ink is dirty and needs to be cleaned. I use a Q-tip, rubbing alchohol, and air. The problem is that the mirror is way, way, way inside and you need to remove about 40 screws. The first time it took me 4 hours. Today it took me 20 minutes!. I put the instructions on my web site.
http://www.dbconstruction.com/hp2600repair.pdf

BBC