• Code: 50.7
• Display: 50.X Fuser Error Turn off then on
• Description: A fuser error has occurred.
  Fuser pressure release mechanism failure
• Remedy: 1. Verify the fuser is installed correctly and fully seated. 2. Check that fuser connector J705, fuser motor connector J5008, and driver PCA connector J213 are seated correctly. 3. Replace the fuser drive assembly. 4. Replace the DC controller PCA.

• Code: 50.8
• Display: 50.X Fuser Error Turn off then on
• Description: A fuser error has occurred.
  Low 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. If there is no conduction in the subthermistor, measure the resistance between fuser connectors J6007LA-1 and J6007LA-3. If the resistance is not 100 kohms to 3 Mohms, replace the fuser. 6. If there is no conduction in the fuser heater, measure the resistance between fuser connectors J6007LAF-1 and J6007-2. If the resistance is not 5 ohms to 1 kohms (100 to 127 V) or 20 ohms to 1 kohms (220 to 240 V), replace the fuser. 7. Replace the DC controller PCA.

• Code: 50.9
• Display: 50.X Fuser Error Turn off then on
• 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 100 kohms to 3 Mohms, replace the fuser. 6. Replace the DC controller PCA.

• Code: 51.20
• Display: 51.XX Error Turn off then on
• Description: A printer error has occurred. Laser Black
• Remedy: 1. Press OK to continue. 2. If the message persists, turn the printer off and then on. 3. Reseat DC controller connectors J1010, J1012, and J1021. 4. Replace the flat cable. 5. Replace the DC controller PCA as necessary.

• Code: 51.21
• Display: 51.XX Error Turn off then on
• Description: A printer error has occurred. Laser Cyan
• Remedy: 1. Press OK to continue. 2. If the message persists, turn the printer off and then on. 3. Reseat DC controller connectors J1010, J1012, and J1021. 4. Replace the flat cable. 5. Replace the DC controller PCA as necessary.

• Code: 51.22
• Display: 51.XX Error Turn off then on
• Description: A printer error has occurred. Laser Yellow
• Remedy: 1. Press OK to continue. 2. If the message persists, turn the printer off and then on. 3. Reseat DC controller connectors J1010, J1012, and J1021. 4. Replace the flat cable. 5. Replace the DC controller PCA as necessary.

• Code: 51.23
• Display: 51.XX Error Turn off then on
• Description: A printer error has occurred. Laser Magenta
• Remedy: 1. Press OK to continue. 2. If the message persists, turn the printer off and then on. 3. Reseat DC controller connectors J1010, J1012, and J1021. 4. Replace the flat cable. 5. Replace the DC controller PCA as necessary.

• 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 DC controller PCA.