HP LaserJet Enterprise 700 Color MFP M775f

[RenCan]

I have an HP 700 series Color M775f, The printer prints a color image without problems, but if I print in black and white, the image is partial
the black cartridge is good.
Can you tell me what the problem is?

[Valsimot]

Can you scan a A4 sample of your black image and post here?

[RenCan]

[Valsimot]

Can you print supplies status page scan and post here?

Do you know how to run an engine test?

[RenCan]

these are the consumption printouts the others are the black and white and color prints, the nuance comes out in the color

[RenCan]

Sorry I sent print with data not allowed
I am also attaching the color diagnosis and alignment, I have deleted the data that should not be seen.

[Valsimot]

I would say that your printer might have a toner disengagement-developing issue. When printing in colour it works fine, but when printing in black white the black toner isn't engaged it a correct angle and you get bad black&white printout.

Can you remove all 4 toners and take a picture of the interior of the printer (the backside of the interior where the gears are)?

It is possible to notice a difference between black and another toner if my assumption is good.

btw. if I am right your printer will need to be disassembled a lot not an easy task.     

[RenCan]

here are the pictures

[Valsimot]

It's not visible as I thought it would be. Can you compare in the red circle is that metal shaft more to the left than other 3, and is the gap with orange dots wider on the 3 colours than on the black toner side?

[RenCan]

I HAVE DONE THE PICTURE OF EVERY COLOR, YOU SEE THE COLOR AT THE BOTTOM

CYANYELLOWMAGENTABLACK