HP 4600- Two colors misaligned , Calib. made it worse

[DCO57]

Guys,
I've had issues with this printer for months now...always the same problem...one or two colors are printing about 1/4" lower than everything else. I replaced the lasers, toner, DC controller, formatter (and RAM/ SRAM), and experimented with the brackets that hold the lasers in place and other misc hardware that may affect the aim of the lasers.
On two occassions I fixed it, but the problem keeps returning.
Has anyone heard of anything like this?
I was thinking of next checking the voltages from the PSU...maybe its putting out high or low voltages and slowly frying the controller.
Any suggestions would be greatly apprecaiated.
DCO57 - IT Dept / AZ Inc

[MichaelTech]

Doing the same with one of these. Had a hard scanner error, and replaced the cyan. Still there. DC=no change. H/V=no change. Then a color registration error, replaced it. No change.
Getting another scanner will see if that does it.

Do a cartridge swap check to see if it follows a toner, or is in only one scanner.
I think shipping damage is what is giving a lot of stuff we order a problem.

[DCO57]

I tried swapping the toners - no go...it doesn't follow the color.
This time (this is the 3rd time this has happened with this printer), the color offset started with the blue then the next day the yellow went out of wack.
After replacing 2 DC controllers - each time fixing it for a month or two before it gradually goes bad again, I can't help but think something is killing the DC controller...slowly. I'm leaning towards a LVPS. Or maybe a cable is grounding out somewhere (that will be fun traceing).
Thanks for your input

[prntrfxr]

be careful when replacing scanners. You need to put a cardboard support for the frame when installing or frame will bend from weight and it will screw up the optics. See service manual - laser scanner replacement for details. I had to add installation instructions on all my refurb scanners for this reason. The frame doesnt have to be bent much to cause the problem.

This may or may not be your problem, but it could make things worse.