• Code: 31
• Description: Density sensor error
• Causes: 1 Harness connection failure of registration mark L PCB ASSY. 2 Harness connection failure of density sensor shutter solenoid. 3 Registration mark L PCB failure. 4 Engine PCB failure. 5 Main PCB failure
• Remedy: 1 Harness connection failure of registration mark L PCB ASSY Check the harness connection between the registration mark L PCB ASSY and registration mark relay PCB ASSY, and the one between the registration mark relay PCB ASSY and engine PCB ASSY. Then, reconnect them. 2 Harness connection failure of density sensor shutter solenoid Check the harness connection of the density sensor shutter solenoid and reconnect it. 3 Registration mark L PCB failure Replace the registration sensor holder ASSY. 4 Engine PCB failure Replace the engine PCB ASSY. 5 Main PCB failure Replace the main PCB ASSY.

• Code: 32
• Description: Density sensor shutter performance malfunction
• Causes: 1 Harness connection failure of registration mark L PCB ASSY. 2 Harness connection failure of density sensor shutter solenoid. 3 Registration mark L PCB failure. 4 Engine PCB failure. 5 Main PCB failure
• Remedy: 1 Harness connection failure of registration mark L PCB ASSY Check the harness connection between the registration mark L PCB ASSY and registration mark relay PCB ASSY, and the one between the registration mark relay PCB ASSY and engine PCB ASSY. Then, reconnect them. 2 Harness connection failure of density sensor shutter solenoid Check the harness connection of the density sensor shutter solenoid and reconnect it. 3 Registration mark L PCB failure Replace the registration sensor holder ASSY. 4 Engine PCB failure Replace the engine PCB ASSY. 5 Main PCB failure Replace the main PCB ASSY.

• Code: 33
• Description: Right color registration sensor error
• Causes: 1 Harness connection failure of registration mark PCB ASSY. 2 Registration mark PCB failure. 3 Engine PCB failure. 4 Main PCB failure.
• Remedy: 1 Harness connection failure of registration mark PCB ASSY Check the harness connection of the registration mark PCB ASSY and reconnect it. 2 Registration mark PCB failure Check the performance of the registration mark sensor following the procedure described in “Function code 75”. If any problem occurs, replace the registration sensor holder ASSY. 3 Engine PCB failure Replace the engine PCB ASSY. 4 Main PCB failure Replace the main PCB ASSY.

• Code: 34
• Description: Left color registration sensor error
• Causes: 1 Harness connection failure of registration mark PCB ASSY. 2 Registration mark PCB failure. 3 Engine PCB failure. 4 Main PCB failure.
• Remedy: 1 Harness connection failure of registration mark PCB ASSY Check the harness connection of the registration mark PCB ASSY and reconnect it. 2 Registration mark PCB failure Check the performance of the registration mark sensor following the procedure described in “Function code 75”. If any problem occurs, replace the registration sensor holder ASSY. 3 Engine PCB failure Replace the engine PCB ASSY. 4 Main PCB failure Replace the main PCB ASSY.

• Code: 36
• Description: HVPS PCB error in ready state
• Causes: 1 Dirt on drum unit electrodes. 2 Harness connection failure of high-voltage power supply PCB ASSY. 3 HVPS control PCB failure. 4 High-voltage power supply PCB failure. 5 Engine PCB failure. 6 Main PCB failure.
• Remedy: 1 Dirt on drum unit electrodes Clean the electrodes of the drum unit and main body. (Refer to Fig. 3-3 (P3-32) and Fig. 3-6 (P3-33).) 2 Harness connection failure of high-voltage power supply PCB ASSY Check the harness connection between the high-voltage power supply PCB ASSY and engine PCB ASSY, and the one between the high-voltage power supply PCB ASSY and main PCB ASSY. Then, reconnect them. 3 HVPS control PCB failure Replace the HVPS control PCB ASSY. 4 High-voltage power supply PCB failure Replace the high-voltage power supply PCB ASSY. 5 Engine PCB failure Replace the engine PCB ASSY. 6 Main PCB failure Replace the main PCB ASSY.

• Code: 37
• Description: Belt thermistor error
• Causes: 1 Harness connection failure of belt thermistor ASSY. 2 Main PCB failure.
• Remedy: 1 Harness connection failure of belt thermistor ASSY Check the harness connection of the belt thermistor ASSY and reconnect it. 2 Main PCB failure Replace the main PCB ASSY.

• Code: 38
• Description: External temperature sensor error
• Causes: 1 Main PCB failure
• Remedy: 1 Harness connection failure of engine PCB ASSY Check the harness connection between the main PCB ASSY and engine PCB ASSY, and reconnect it. 2 Engine PCB failure Replace the engine PCB ASSY. 3 Main PCB failure Replace the main PCB ASSY.

• Code: 39
• Description: External humidity sensor error
• Causes: 1 Main PCB failure
• Remedy: 1 Harness connection failure of engine PCB ASSY Check the harness connection between the main PCB ASSY and engine PCB ASSY, and reconnect it. 2 Engine PCB failure Replace the engine PCB ASSY. 3 Main PCB failure Replace the main PCB ASSY.