(2) All-black printout
Check the main charger.
•Open the printer top cover and check that the process unit is correctly seated. Poor contact main charger terminal between the process unit and the printer main unit.
Check the drum bias.
• Make sure the bias from the high voltage board correctly arrives at the process unit.
Check high voltage potential at the high voltage board.
•Check the high voltage output on the high voltage board. Replace the high voltage board if high voltage potential is not available on the board.