• Code: 50.9
• Display: 50.X FUSER ERROR
• Description: A fuser error has occurred.
  High fuser temperature (subthermistor)
• Remedy: 1. Verify the fuser is installed correctly and fully seated. 2. Check that connector J6007 on the fuser is seated correctly. Replace the connector as necessary. 3. Turn off the printer. 4. Remove the fuser. 5. Measure the resistance between fuser connectors J6007LA-2 and J6007LA-3. If the resistance is not 368 to 522 kohms, replace the fuser. 6. Replace the DC controller PCA.

• Code: 51.20
• Display: 51.2Y ERROR
• Description: A printer error has occurred.
  Black
• Remedy: 1. Press to continue. 2. If the message persists, turn the printer off and then on. 3. Reseat DC controller connectors J1010, J1012, and J1021. Reseat laser/ scanner unit connectors J101, J102, J5001A, and J5001B. 4. Replace the flat cable. 5. Replace the laser/scanner unit as necessary. 6. Replace the DC controller PCB as necessary.

• Code: 51.21
• Display: 51.2Y ERROR
• Description: A printer error has occurred.
  Cyan
• Remedy: 1. Press to continue. 2. If the message persists, turn the printer off and then on. 3. Reseat DC controller connectors J1010, J1012, and J1021. Reseat laser/ scanner unit connectors J101, J102, J5001A, and J5001B. 4. Replace the flat cable. 5. Replace the laser/scanner unit as necessary. 6. Replace the DC controller PCB as necessary.

• Code: 51.22
• Display: 51.2Y ERROR
• Description: A printer error has occurred.
  Yellow
• Remedy: 1. Press to continue. 2. If the message persists, turn the printer off and then on. 3. Reseat DC controller connectors J1010, J1012, and J1021. Reseat laser/ scanner unit connectors J101, J102, J5001A, and J5001B. 4. Replace the flat cable. 5. Replace the laser/scanner unit as necessary. 6. Replace the DC controller PCB as necessary.

• Code: 51.23
• Display: 51.2Y ERROR
• Description: A printer error has occurred.
  Magenta
• Remedy: 1. Press to continue. 2. If the message persists, turn the printer off and then on. 3. Reseat DC controller connectors J1010, J1012, and J1021. Reseat laser/ scanner unit connectors J101, J102, J5001A, and J5001B. 4. Replace the flat cable. 5. Replace the laser/scanner unit as necessary. 6. Replace the DC controller PCB as necessary.

• Code: 53.10.01
• Display: 53.10.01 ERROR UNSUPPORTED RAM
• Description: For the HP Color LaserJet 3000 and 3800 Series printers only The memory DIMM is not a supported DIMM.
• Remedy: Install a supported DIMM.

• Code: 53.XY.ZZ
• Display: 53.XY.ZZ
• Description: For the HP Color LaserJet 3600 Series printer only A printer error has occurred.
• Remedy: 1. Turn the printer off and then on. 2. If the message persists, replace the DIMM. 3. Replace the formatter.

• Code: 54.15
• Display: 54.XX ERROR
• Description: An error has occurred with one of the tonerlevel sensors.
  Yellow
• Remedy: 1. Make sure that connector J1020 on the DC controller is seated correctly. 2. Replace the memory-controller PCA. 3. Replace the DC controller.