The Magenta Ink Isn't Coming Out During Printing.

Thanks

- open the service window to purge the MAGENTA printheads
- purge them until all ink is out of subtank.
- remove the connection of magenta ink subtanks and put them into one empty bottle of water or beaverage.
- close the service window.
- after that the magenta ink pump must start to pump until the subtank get full.
- check each ink line on the bottle if they are receiving just ink or ink with bubles.
- just ink -> open the service window to stop the pump. Replace the ink filter on the reservoir that must be getting clogged.
- ink with bubles - got to the reservoir and retight the ink filter that must be lose causing the issue. replace them if necessary.

https://support.hp.com/us-en/product/hp-scitex-xl1500-industrial-printer-series/3340920/videos

It is not exactly helpful but one suggestion I have is that if you remove the ink cartridges and see if the printhead assembly is removable it may be possible to clean it under running water. This works with home inkjets but I cannot guarantee the same result with these industrial models. The other alternative is to purchase cleaning cartridges for your printer which you insert in place of the normal ink cartridges and they perform a similar function. If all else fails then a replacement head assembly may be required. A check with spares suppliers may give results.

Hope that helps.