My 7880 is equipped with the P2 Selenium ink set.
About a month ago, I replaced all eight Ink Holder Assemblies. Everything was running perfectly until yesterday. In the past week, I made about twenty-five perfect 13 x 19 prints.
But, while applying GO to one of those last prints, I got some black ink polluting the first half inch of the leading edge. I figured ink had built up on the print head, so, I performed Dana’s Piezoflush cleaning procedure on the print head, cap station, wiper blade, and box unit.
Then, I did an Auto Nozzle Check (see attached). It’s clean except it clearly shows the Light Black channel losing dots with each attempt to automatically correct the problem.
So, I’ve performed multiple power cleanings from the Adjustment Program— no improvement.
I replaced the Light Black damper—still no improvement.
The Epson 7880 service manual states the following:
When the dots missing appears in particular colors.
Check the Head Cleaner for any dirt. (did that‚ it’s clean as a whistle)
Check the junctions of the ink cartridges, Ink Holder, tubes, dampers, and the printhead for any abnormality. (Ink may be leaking by loosened fixing nuts, deformed or damaged O-ring. (no visible leaks, air pockets in tubing, or damaged O-rings)
Check if the printhead is defective. (not sure how to do this)
Perform the power cleaning again.
If the trouble still occurs even after performing all the troubleshooting described above, replace the parts listed below and check if it returns the printer to normal.
• PRINT HEAD
• BOARD ASSY., MAIN
Would you kindly share any tips for checking the printhead for possible defects? Or, any other remedies for missing dots in one channel?