HP Color LaserJet 9500 Printer series - Manual (Page 170)

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168 Chapter 6 – Solving problems Rev. 1.0
8X.YYYY The EIO accessory card in slot X has
encountered a critical error as specified by
YYYY .
Turn the printer off.
Remove the EIO accessory card.
Reseat the card securely into the
specified slot.
Turn the printer on.
If the message persists, the EIO
accessory card might need to be
replaced.
Message Description or explanation Recommended action