• Code: 55.01.YY
• Display: 55.XX.YY DC CONTROLLER ERROR - To Continue Turn Off Then On
• Description: The print engine is not communicating with the formatter.
  Incoming parity error
• Remedy: Turn the MFP off, and then turn the MFP on.

• Code: 55.02.YY
• Display: 55.XX.YY DC CONTROLLER ERROR - To Continue Turn Off Then On
• Description: The print engine is not communicating with the formatter.
  Outgoing parity error
• Remedy: Turn the MFP off, and then turn the MFP on.

• Code: 55.04.YY
• Display: 55.XX.YY DC CONTROLLER ERROR - To Continue Turn Off Then On
• Description: The print engine is not communicating with the formatter.
  Communications timeout
• Remedy: Turn the MFP off, and then turn the MFP on.

• Code: 55.05
• Display: 55.05 Error - To continue turn off then on
• Description: This Remote Firmware Upgrade (RFU) error message occurs when an upgrade on the firmware is being performed and something has happened that prevented the upgrade.
• Remedy: Turn the MFP off, and then turn the MFP on.

• Code: 56.1
• Display: 56.X ERROR - To Continue Turn Off Then On
• Description: The input device or output device is unknown.
  Unknown input device
• Remedy: 1. Turn the MFP off, and then turn the MFP on. 2. For 56.1 errors, reinstall all of the input devices (optional 500-sheet feeders or the envelope feeder.) For 56.2 errors, reinstall the output bin, the stapler/ stacker, or the 3-bin mailbox. 3. Remove all non-HP paper-handling devices.

• Code: 56.2
• Display: 56.X ERROR - To Continue Turn Off Then On
• Description: The input device or output device is unknown.
  Unknown output device
• Remedy: 1. Turn the MFP off, and then turn the MFP on. 2. For 56.1 errors, reinstall all of the input devices (optional 500-sheet feeders or the envelope feeder.) For 56.2 errors, reinstall the output bin, the stapler/ stacker, or the 3-bin mailbox. 3. Remove all non-HP paper-handling devices.

• Code: 57.01
• Display: 57.01 Error - To continue turn off then on
• Description: The DC controller fan (FN104) is not functioning.
• Remedy: 1. Verify that the connector J66 on the DC controller is firmly seated. 2. Listen for the fan to operate while the MFP is initializing. 3. If the fan does not operate during the initialization sequence, replace it.

• Code: 57.03
• Display: 57.03 Error - To continue turn off then on
• Description: The print-cartridge fan (FN102) is not functioning.
• Remedy: 1. Verify that the connector J78 on the DC controller is firmly seated. 2. Listen for the fan to operate while the MFP is initializing. 3. If the fan does not operate during the initialization sequence, replace it.