As these printers age, they do get alignment issues.
This procedure turns of the ink counters which will disable one of the wires on the ink sensors. It may be the solution although I haven’t touched one of these printers in over a decade so can’t say for sure.
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How Turn off the ink counter on your 7600/9600
The printer will come Ready with a ‘O’ at the left of the ink cartridge status bars on the LCD.
The status of all ink cartridges will always show full.
This setting is written to the e-prom and does not change if the power is cycled.
Remember that with the big 220ml carts you would only need to use a chip resetter fairly infrequently.
Warning – getting this wrong could well mess up your printer, so do it at your own risk (this info is from Lyson and they won’t take responsibility for damage either!)
Start with the printer powered OFF.
Press and hold the PAPER SOURCE, PAPER FEED DOWN und CUT/EJECT buttons and power up the printer.
When the LCD display shows ‘VIEW COUNTERS’, release all the buttons.
Press PAPER FEED DOWN, until you can see SERVICE CONFIG on the LCD display.
Press the SELEC TYPE button once.
Press the PAPER FEED DOWN button until the LCD display reads ED MODE.
Press the ENTER button
The display now reads * X.
Press the PAPER FEED DOWN button until the display reads O.
Press the ENTER button, and the display will read * O.
Turn the printer off.
Turn the printer on.