• Code: C6740
• Description: IH PWB high temperature error (IGBT2) The IGBT temperature acquired from the power microprocessor detected is 115°C / 239°F or more for 1s continuously.
• Remedy: 1 Checking the IH PWB fan motor The connection of the IH PWB fan motor, or the IH PWB fan motor is faulty. Execute U037 [IH PWB] and check the operation of the fan motor of the IH PWB. If it is not operating, move to the step2 [connect fan motor of the IH PWB]. If it is operating, move to the step3 [replace fan motor of the IH PWB]. 2 Connecting the IH PWB fan motor The connector of the IH PWB fan motor wire is not inserted securely. Reinsert the connector of the IH PWB fan motor. 3 Replacing the IH PWB fan motor The IH PWB fan motor is faulty. Replace the IH PWB fan motor. Fan Motors Attachable Direction 4 Checking the connection The connector is not connected properly, or the wire is faulty. Clean the terminal of the following wire connectors and reconnect the connectors. If there is no continuity, replace the wire. . IH PWB - Engine PWB Section 8 "PWBs" 5 Replacing the IH PWB The IH PWB is faulty. Replace the IH PWB. Detaching and reattaching the IH PWB 6 Firmware upgrade The firmware is not the latest version. Upgrade the engine firmware to the latest version Firmware Update 7 Replacing the engine PWB The engine PWB is faulty. Replace the engine PWB. Detaching and reattaching the Engine PWB

• Code: C6760
• Description: Fuser IH input excessive electric current error The input current obtained from the power microcomputer was 20A (100/120V) or 10A (200V) or more continued for 200ms.
• Remedy: 1 Checking the fuser unit The fuser belt is faulty. Detach the fuser unit and check if the fuser belt is not faulty. If there is any damage, replace the fuser unit. Detaching and reattaching the Fuser Unit 2 Checking the connection The connector is not connected properly, or the wire is faulty. Clean the terminal of the following wire connectors and reconnect the connectors. If there is no continuity, replace the wire. . IH PWB - Engine PWB Section 8 "PWBs" 3 Firmware upgrade The firmware is not the latest version. Upgrade the engine firmware to the latest version Firmware Update 4 Replacing the IH PWB The IH PWB is faulty. Replace the IH PWB. Detaching and reattaching the IH PWB 5 Replacing the fuser unit The fuser unit is faulty. Replace the fuser unit. Detaching and reattaching the Fuser Unit 6 Replacing the engine PWB The engine PWB is faulty. Replace the engine PWB. Detaching and reattaching the Engine PWB

• Code: C6770
• Description: IH low power error After fuser unit is started to heat, fuser rotation pulse signal cant be detected continuously for 1s.Or, no electric powers supplied to IH fuse runit.(Electric power detection on the IHPWB detected a set electric powe rvalue of 30% or less for a predetermined time.)'
• Remedy: 1 Checking the connection The connector is not connected properly, or the wire is faulty. Clean the terminal of the following wire connectors and reconnect the connectors. If there is no continuity, replace the wire. . Fuser IH unit - IH PWB . IH PWB - Engine PWB . Feed image PWB - Engine PWB Section 8 "PWBs" 2 Checking the fuser unit drawer connectors The fuser unit drawer connectors are not properly connected. If foreign objects adhere on the drawer pins of each drawer connector, clean the drawer pins. If the drawer pins are deformed, repair or replace it. . In case the drawer pins in the fuser unit are faulty and they cannot be repaired by cleaning and fixing: Replace the fuser unit. . In case the drawer pins in the main unit are faulty and they cannot be repaired by cleaning and fixing: Replace the wire. (Part no.: 302ND4637_). If the drawer pins are not faulty, reinstall the fuser unit into the main unit so that the drawer connectors connect each other firmly. Detaching and reattaching the Fuser Unit 3 Replacing the IH PWB The IH PWB is faulty. Replace the IH PWB. Detaching and reattaching the IH PWB 4 Firmware upgrade The firmware is not the latest version. Upgrade the engine firmware to the latest version Firmware Update 5 Replacing the engine PWB The engine PWB is faulty. Replace the engine PWB. Detaching and reattaching the Engine PWB 6 Replacing the feed image PWB The feed image PWB is faulty. Replace the feed image PWB. 7 Checking the cause depending on the input power The input power is improper. Change the input power. 8 Replacing the fuser IH unit The fuser IH unit is faulty. (The coil is broken.) Replace the fuser IH unit. 9 Replacing the fuser unit The belt rotation sensor in the fuser unit is faulty. The thermostat is broken. Replace the fuser unit. Detaching and reattaching the Fuser Unit

• Code: C6900
• Description: Edge fan motor error The lock-up was detected for 20s continuously when driving the fan motor.
• Remedy: 1 Checking the edge fan motor The connector is not connected properly. The wire is faulty. The fan does not operate as paper size on the MP tray is misdetected. Execute U037 [Fuser Edge] to check the edge fan motor operation. And, check if the paper size on the MP tray is detected properly. If the edge fan motor does not operate properly or the paper size on the MP tray is misdetected, reconnect the connector of the conveying unit (edge fan motor) to the relay connector at the main unit. Maintenanc e Mode List Detaching and reattaching the Right Cover Assy 2 Checking the connection The connector is not connected properly, or the wire is faulty. Clean the terminal of the following wire connectors and reconnect the connectors. If there is no continuity, replace the wire. . Edge fan motor - Feed drive PWB . Feed drive PWB - Engine PWB Section 8 "PWBs" 3 Replacing the edge fan motor The edge fan motor is faulty. Replace the edge fan motor. Fan Motors Attachable Direction 4 Firmware upgrade The firmware is not the latest version. Upgrade the engine firmware to the latest version Firmware Update 5 Replacing the feed drive PWB The feed drive PWB is faulty. Replace the feed drive PWB. 6 Replacing the engine PWB The engine PWB is faulty. Replace the engine PWB. Detaching and reattaching the Engine PWB

• Code: C6910
• Description: Engine firmware unexpected error 1. The engine stabilization control continued for 1 hour. 2. The feed motor does not drive even passing 3s or more when driving the drum motor or the developer K/transfer belt motor. 3. Only the high-voltage remote signal turned on under the condition that the drum is stopped. 4. The main charger bias turned off while the developer bias was on.
• Remedy: 1 Resetting the main power The power startup delays. Turn the power switch and the main power switch off . After 5s passes, turn the main power switch and the power switch on. 2 Firmware upgrade The firmware is not the latest version. Upgrade the engine firmware to the latest version Firmware Update 3 Checking the engine PWB The engine PWB is not properly attached or connected. Retighten the screws securing the engine PWB so that it can ground securely, and reinsert the connectors all the way. Detaching and reattaching the Engine PWB 4 Replacing the engine PWB The engine PWB is faulty. Replace the engine PWB. Detaching and reattaching the Engine PWB

• Code: C6920
• Description: Eject/IH fan motor error The lock-up was detected for 20s continuously when driving the fan motor.
• Remedy: 1 Checking the connection The connector is not connected properly, or the wire is faulty. Execute U037 [Exit Paper IH Coil]. If the following fan motor does not operate properly, clean the terminal of the connector and reconnect the connector. If there is no continuity, replace the wire. . Exit/IH front fan motor - Feed image PWB . Exit/IH middle fan motor - Feed image PWB . Exit/ IH rear fan motor - Feed image PWB . Feed image PWB - Engine PWB Maintenanc e Mode List Section 8 "PWBs" 2 Checking the eject/IH fan motors The eject/IH fan motors do not properly operate. Clean the following fan motors, and remove foreign objects if they adhere on the fan motor. If not repaired after that, replace the fan motor. . Exit/IH front fan motor . Exit/IH middle fan motor . Exit/IH rear fan motor Fan Motors Attachable Direction 3 Firmware upgrade The firmware is not the latest version. Upgrade the engine firmware to the latest version Firmware Update 4 Replacing the feed image PWB The feed image PWB is faulty. Replace the feed image PWB. 5 Replacing the engine PWB The engine PWB is faulty. Replace the engine PWB. Detaching and reattaching the Engine PWB

• Code: C6950
• Description: IH PWB communication error 1. Communication between the IH PWB and the engine PWB is not established in the initial communication. (150ms interval x 10 times retries are performed) 2. After the initial communication is established, communication between the IH PWB and the engine PWB is not established. (For 500ms)
• Remedy: 1 Resetting the main power The power startup delays. Turn the power switch and the main power switch off . After 5s passes, turn the main power switch and the power switch on. 2 Checking the connection The connector is not connected properly. Or, the wire is faulty. (Power supply failure to the IH PWB or communication error by the grounding failure.) Clean the terminal of the following wire connectors and reconnect the connectors. If there is no continuity, replace the wire. . Low voltage PWB - IH PWB . IH PWB - Engine PWB Section 8 "PWBs" 3 Checking the power supply voltage The abnormal electric noise is mixed in the power supply voltage. Plug the power cord into another wall outlet.4 Checking the low voltage PWB The fuse on the low voltage PWB is broken. Check the continuity of the fuse (F002) on the low voltage PWB. Then, replace the low voltage PWB if there is no continuity. Detaching and reattaching the Low Voltage PWB 5 Replacing the IH PWB The IH PWB is faulty. Replace the IH PWB. Detaching and reattaching the IH PWB 6 Firmware upgrade The firmware is not the latest version. Upgrade the engine firmware to the latest version Firmware Update 7 Replacing the engine PWB The engine PWB is faulty. Replace the engine PWB. Detaching and reattaching the Engine PWB

• Code: C6980
• Description: Fuser unit EEPROM error It is not possible to access the fuser unit EEPROM since it matches one of the following. 1. Five times consecutive detection of no response from the device for more than 5ms on reading / writing. 2. Data read in 2 places does not match 8 consecutive times. 3. Writing data and reading data does not match 8 consecutive times.
• Remedy: 1 Checking the fuser unit drawer connectors The fuser unit drawer connectors are not properly connected. If foreign objects adhere on the drawer pins of each drawer connector, clean the drawer pins. If the drawer pins are deformed, repair or replace it. . In case the drawer pins in the fuser unit are faulty and they cannot be repaired by cleaning and fixing: Replace the fuser unit. . In case the drawer pins in the main unit are faulty and they cannot be repaired by cleaning and fixing: Replace the wire. (Part no.: 302ND4637_). If the drawer pins are not faulty, reinstall the fuser unit into the main unit so that the drawer connectors connect each other firmly. Detaching and reattaching the Fuser Unit 2 Replacing the fuser unit The fuser unit is faulty. Replace the fuser unit. Detaching and reattaching the Fuser Unit 3 Replacing the engine PWB The engine PWB is faulty. Replace the engine PWB. Detaching and reattaching the Engine PWB 4 Replacing the feed image PWB The feed image PWB is faulty. Replace the feed image PWB.