• Code: 69
• Description: Fuser unit failure (The side thermistor detects lower temperature than the specified value.)
• Causes: Fuser unit harness connection failure. Fuser unit failure. LVPS PCB unit failure. Main PCB failure.
• Remedy: 1 Fuser unit harness connection failure Check the harness connection of the fuser unit and reconnect it. 2 Fuser unit failure Replace the fuser unit. 3 LVPS PCB unit failure Replace the LVPS PCB unit. 4 Main PCB failure Replace the main PCB ASSY.

• Code: 6A
• Description: Fuser unit failure (The side thermistor does not detect 60°C within the specified time.)
• Causes: Fuser unit harness connection failure. Fuser unit failure. LVPS PCB unit failure. Main PCB failure.
• Remedy: 1 Fuser unit harness connection failure Check the harness connection of the fuser unit and reconnect it. 2 Fuser unit failure Replace the fuser unit. 3 LVPS PCB unit failure Replace the LVPS PCB unit. 4 Main PCB failure Replace the main PCB ASSY.

• Code: 6B
• Description: Fuser unit failure (The center thermistor does not detect 100°C within the specified time.)
• Causes: Fuser unit harness connection failure. Fuser unit failure. LVPS PCB unit failure. Main PCB failure.
• Remedy: 1 Fuser unit harness connection failure Check the harness connection of the fuser unit and reconnect it. 2 Fuser unit failure Replace the fuser unit. 3 LVPS PCB unit failure Replace the LVPS PCB unit. 4 Main PCB failure Replace the main PCB ASSY.

• Code: 6C
• Description: Fuser unit failure (The center thermistor detects higher temperature than the specified value.)
• Causes: Fuser unit harness connection failure. Fuser unit failure. LVPS PCB unit failure. Main PCB failure.
• Remedy: 1 Fuser unit harness connection failure Check the harness connection of the fuser unit and reconnect it. 2 Fuser unit failure Replace the fuser unit. 3 LVPS PCB unit failure Replace the LVPS PCB unit. 4 Main PCB failure Replace the main PCB ASSY.

• Code: 6D
• Description: Fuser unit failure (The center thermistor detects lower temperature than the specified value.)
• Causes: Fuser unit harness connection failure. Fuser unit failure. LVPS PCB unit failure. Main PCB failure.
• Remedy: 1 Fuser unit harness connection failure Check the harness connection of the fuser unit and reconnect it. 2 Fuser unit failure Replace the fuser unit. 3 LVPS PCB unit failure Replace the LVPS PCB unit. 4 Main PCB failure Replace the main PCB ASSY.

• Code: 6E
• Description: Fuser unit failure (The center thermistor does not detect temperature rising within the specified time.)
• Causes: Fuser unit harness connection failure. Fuser unit failure. LVPS PCB unit failure. Main PCB failure.
• Remedy: 1 Fuser unit harness connection failure Check the harness connection of the fuser unit and reconnect it. 2 Fuser unit failure Replace the fuser unit. 3 LVPS PCB unit failure Replace the LVPS PCB unit. 4 Main PCB failure Replace the main PCB ASSY.

• Code: 6F
• Description: Fuser unit failure (The center and side thermistors detect extremely high temperature.)
• Causes: Fuser unit harness connection failure. Fuser unit failure. LVPS PCB unit failure. Main PCB failure.
• Remedy: 1 Fuser unit harness connection failure Check the harness connection of the fuser unit and reconnect it. 2 Fuser unit failure Replace the fuser unit. 3 LVPS PCB unit failure Replace the LVPS PCB unit. 4 Main PCB failure Replace the main PCB ASSY.

• Code: 71
• Description: Laser unit Polygon mirror motor failure (Cannot detect the period signal of the polygon mirror motor.)
• Causes: Laser unit harness connection failure. Laser unit failure. Main PCB failure.
• Remedy: 1 Laser unit harness connection failure Check the two harness connections of the laser unit and reconnect them. 2 Laser unit failure Replace the laser unit. 3 Main PCB failure Replace the main PCB ASSY.