• Code: 935
• Description: Black Drum Sensor Error
• Remedy: 1 Is connector CN27 connected properly? Go to step 2. Plug the connector in securely.
  2 Clean the black drum sensor LED. Did this fix the problem? Problem solved. Replace the black drum sensor. Go to step 3.
  3 Did replacing the black drum sensor fix the problem? Problem solved. Replace the printer controller board.

• Code: 936...939
• Description: Cassette Error
• Remedy: 1 Are connectors CN35 and CN36 on the printer controller board connected properly? Replace the printer controller board. Plug the connector in securely.

• Code: 940
• Description: High-Capacity Feed Sensor Error
• Remedy: 1 Is connector CN40 on the printer controller board connected properly? Go to “Highcapacity feeder (HCF) service check”. Plug the connector in securely.

• Code: 941
• Description: High-Capacity Feed Tray Error
• Remedy: 1 Is connector CN40 on the printer controller board connected properly? Go to “Highcapacity feeder (HCF) service check”. Plug the connector in securely.

• Code: 942
• Description: Duplex Error
• Remedy: 1 Is connector CN37 on the printer controller board connected properly? Replace the printer controller board. Plug the connector in securely.

• Code: 945
• Description: Engine Flash Error
• Remedy: Reflash the engine code.

• Code: 946
• Description: Printer/Printhead Controller Board Communication Error
• Remedy: 1 Make sure all printhead LED EPROMS are present on the printhead controller board. Are all the EPROMS present? Go to step 2 Replace the EPROMS.
  2 Replace the printhead controller board. Did this fix the problem? Problem solved. Replace the printer controller board.

• Code: 947
• Description: Finisher Communication Error
• Remedy: 1 Are the finisher to printer interface cable and power cable properly connected? Go to step 2. Properly connect the cable.
  2 Replace the interface cable. Did this resolve the problem? Problem solved. Replace the control finisher board. Go to step 3.
  3 Did finisher control board replacement resolve the problem? Problem solved. Replace the printer control board.