• Code: C6120
• Description: Press/heat roller abnormal high temperature • The temperature on the press/heat roller has risen up to the predetermined abnormal temperature.
• Causes: Defective engine controller PCB. Defective lower fuser heater. Defective fuser PCB. Defective lower fuser thermistor. Defective power supply unit. Defective AC power source (abnormal high voltage). Defective harness between engine controller PCB and fuser unit, or poor contact of the connector terminals.
• Remedy: Replace the engine controller PCB and check for correct operation. Replace the fuser unit (lower fuser heater). Replace the fuser unit (fuser PCB). Replace the lower fuser thermistor. Replace the power supply unit. Connect to the proper AC power source. Check the continuity of the harness and the insertion of connectors.

• Code: C6130
• Description: Lower fuser thermistor broken detection • The temperature detection is not obtained from the lower fuser thermistor.
• Causes: Defective engine controller PCB. Defective fuser PCB. Defective lower fuser thermistor, or improper fitting. Defective harness between engine controller PCB and fuser unit (lower fuser thermistor), or poor contact of the connector terminals.
• Remedy: Replace the engine controller PCB and check for correct operation. Replace the fuser unit (fuser PCB). Replace the fuser unit (lower fuser thermistor). Check the continuity of the harness and the insertion of connectors.

• Code: C6140
• Description: Lower fuser thermistor abnormal temperature detection • The temperature detection output from the lower fuser thermistor is out of the normal range.
• Causes: Defective engine controller PCB. Defective fuser PCB. Defective lower fuser thermistor, or fitting is not proper. Defective harness between engine controller PCB and fuser unit (lower fuser thermistor), or poor contact of the connector terminals.
• Remedy: Replace the engine controller PCB and check for correct operation. Replace the fuser unit (fuser PCB). Replace the fuser unit (lower fuser thermistor). Check the continuity of the harness and the insertion of connectors.

• Code: C7001
• Description: Black toner feed motor lock • The revolution of the black toner feed motor does not reach the predetermined revolution within the predetermined period when ASIC (U8) on the engine controller PCB activates the black toner feed motor.
• Causes: Defective engine controller PCB. Defective black developer (Black developer PCB). Defective harness between engine controller PCB and black developer, or poor contact of the connector terminals.
• Remedy: Replace the engine controller PCB and check for correct operation. Replace the black developer. Check the continuity of the harness and the insertion of connectors.

• Code: C7002
• Description: Cyan toner feed motor lock • The revolution of the cyan toner feed motor does not reach the predetermined revolution within the predetermined period when ASIC (U8) on the engine controller PCB activates the cyan toner feed motor.
• Causes: Defective engine controller PCB. Defective cyan developer (cyan developer PCB). Defective harness between engine controller PCB and cyan developer, or poor contact of the connector terminals.
• Remedy: Replace the engine controller PCB and check for correct operation. Replace the cyan developer. Check the continuity of the harness and the insertion of connectors.

• Code: C7003
• Description: Magenta toner feed motor lock • The revolution of the magenta toner feed motor does not reach the predetermined revolution within the predetermined period when ASIC (U8) on the engine controller PCB activates the magenta toner feed motor.
• Causes: Defective engine controller PCB. Defective magenta developer (magenta developer PCB). Defective harness between engine controller PCB and magenta developer, or poor contact of the connector terminals.
• Remedy: Replace the engine controller PCB and check for correct operation. Replace the magenta developer. Check the continuity of the harness and the insertion of connectors.

• Code: C7004
• Description: Yellow toner feed motor lock • The revolution of the yellow toner feed motor does not reach the predetermined revolution within the predetermined period when ASIC (U8) on the engine controller PCB activates the yellow toner feed motor.
• Causes: Defective engine controller PCB. Defective yellow developer (yellow developer PCB). Defective harness between engine controller PCB and yellow developer, or poor contact of the connector terminals.
• Remedy: Replace the engine controller PCB and check for correct operation. Replace the yellow developer. Check the continuity of the harness and the insertion of connectors.

• Code: C7101
• Description: Black T/C sensor toner density detection error • A normal toner density signal is not entered in the A/D port of CPU (U2) on the engine controller PCB.
• Causes: Defective engine controller PCB. Defective black developer (black developer PCB or black T/C sensor). Defective black developer (black toner feed motor does not rotate in the correct revolution) . Defective harness between engine controller PCB and black developer, or poor contact of the connector terminals.
• Remedy: Replace the engine controller PCB and check for correct operation. Replace the black developer. Replace the black developer. Check the continuity of the harness and the insertion of connectors.