Epson 880 ink light refuses to go out

We have an Epson 880 at our school that doesn't want to reset the black
ink-out light once a new cartridge is placed in the ink chamber. The light
iremains on solid red. I have tried repeatedly to lift the clamp cover and
reset it (at least 10 times) but the light will not go out. I even tried
using the old cartridge to see if that would work to reset the ink out
light, thinking that the new cartridge might be physically faulty. That has
not helped.
I'm thinking that there may be a pcb malfunction but am not sure. We are
using the printer with an Apple Emac so even considering using the SSC
utility software to overide the out light would not be relevent as the
software is only used for a PC. Any ideas how to deal with this problem?
By the way, I have several other dead 880 printers on hand to scavenge
should anyone have a possible solution.

Thanks,

Jan Alter

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