M680z Won't Print Black But WIll Print Color

[Bigjimfanning]

Printer will not print in black but will print color. Swapped two OEM toners, ran half test to see if image was writing to the drum. Upon test noticed that image is on colors but not black. Tried new transfer belt, high voltage power supply and HVPS PCA. Nothing. Inspected shudder and verified that Laser Scanner was spinning, which it was. All drum drive motors are functioning normally and there are no error codes.

I am leaning towards the Laser Scanner or something blocking the shudder but after replacing several parts that are non returnable, I am afraid to replace anything else for fear that this will not resolve the issue and will be back to square one.

Any assistance would be greatly appreciated.

[Alex-TATS · Accepted solution]

Hi Bigjimfanning,

- Have you done an engine test? What are the results?

- Inspect the black toner cartridge's slot in the printer, especially the front little spring that makes contact with the toner cartridge. Also, inspect the plastic cover above the toner cartridge slots. It must be in place sitting correctly.

[Bigjimfanning]

Hi Alex,

Thanks for the info. Yes, everything appears to be in the proper place. Have not done an engine test but did cheat the machine to make sure the motor was functioning properly.

[Alex-TATS]

There is a little hole at rear side of printer next to the formatter. If you press and hole something that fits in there for several seconds then an engine test page is printed. Print that page and tell me what it looks like (if there are lines of all 3 colours and black).

[Bigjimfanning]

Did the engine test and this did not help. It produces a series of lines but still no black. For further troubleshooting, I replaced the Laser Scanner, ran multiple tests with the laser scanner cleaner, made sure the plunger was not broken, inspected cartridge connections, ran tests to ensure laser is not being obstructed, replaced the DC controller and still no resolution. At this point, I have replaced every part that could be the source of the issue. It has to be a wireling issue of some kind and the chances of finding that is a needle in a haystack. We have recommended a replacement. It sucks to because this machine was purchased a little over a year ago and the warranty expired in August. The client esssentially just spent $6000 to lease the machine for a year.