• Code: 520
• Description: 2nd BTR malfunction (Advance)
• Remedy: 1 • Initial checking: Is there any parts of wrong specifications used, improper mounting, damage, distortion, dirt, or adherence of foreign matter? • Major parts to be checked: BTR CAM CLUTCH, PRO DRIVE GEAR ASSY BTR WHEEL SENSOR, MCU PWB Replace or reinstall the relevant part. Go to step 2 2 • Checking whether the problem lies in engine or controller: Can a test print (single sheet / consecutive printing, about 10 sheets each) be performed normally with the engine alone? Check the Printer Controller. If an error still occurs after replacing, • With the tool: Go to step 3 • Without the tool: Go to step 4 • With the tool: Go to step 3 • Without the tool: Go to step 4 3 • Checking the PRO Motor: Does the PRO Motor function properly? . By using the diagnostics commander, check by Digital Output Test device code "54". Go to step 5 Go to step 4 4 • Checking the installation of PRO DRIVE GEAR ASSY: Has the PRO DRIVE GEAR ASSY been installed properly? • With the tool: Go to step 5 • Without the tool: Go to step 6 Reinstall the PRO DRIVE GEAR ASSY 5 • Checking the P/R MOT&DRV ASSY: Does the P/R MOT&DRV ASSY function properly? . By using the diagnostics commander, check by Digital Output Test device code "54". Go to step 8 Go to FIP-2.28 “Faulty P/R MOT & DRV ASSY” 6 • Checking the installation of 2ND BTR ASSY: Has the 2ND BTR ASSY been installed properly? Go to step 7 Reinstall the 2ND BTR ASSY 7 • Checking the installation of BTR WHEEL SENSOR: Has the BTR WHEEL SENSOR been installed properly? Go to FIP-2.22 “Faulty BTR CAM CLUTCH” Reinstall the BTR WHEEL SENSOR 8 • Checking the BTR WHEEL SENSOR: Does the BTR WHEEL SENSOR function properly? . By using the diagnostics commander, check by Digital Input Test device code "76". Replace the MCU PWB-XL Replace the BTR WHEEL SENSOR 9 • Checking the BTR CAM CLUTCH: Does the BTR CAM CLUTCH function correctly? . By using the diagnostics commander, check by Digital Output Test device code "70". Replace the MCU PWB-XL Go to FIP-2.22 “Faulty BTR CAM CLUTCH”

• Code: 521
• Description: 2nd BTR malfunction
• Remedy: 1 • Initial checking: Is there any parts of wrong specifications used, improper mounting, damage, distortion, dirt, or adherence of foreign matter? • Major parts to be checked: 2ND BTR, BTR CAM CLUTCH, MCU PWB TRANSFER HIGH ASSY Replace or reinstall the relevant part. Go to step 2 2 • Checking whether the problem lies in engine or controller: Can a test print (single sheet / consecutive printing, about 10 sheets each) be performed normally with the engine alone? Check the Printer Controller. (If an error still occurs after replacing, go to step 3.)] Go to step 3 3 • Checking retraction During the test printing, does the 2ND BTR ASSY retract? • Check the operation of the BTR CAM CLUTCH from the rear side. Go to step 9 • With the tool: Go to step 4 • Without the tool: Go to step 5 4 • Checking the BTR CAM CLUTCH: Does the BTR CAM CLUTCH function correctly? . By using the diagnostics commander, check by Digital Output Test device code "27". Go to step 9 Go to FIP-2.22 “Faulty BTR CAM CLUTCH” 5 • Checking the installation of BTR CAM CLUTCH: Has the BTR CAM CLUTCH been installed properly? Go to step 6 Reinstall the BTR CAM CLUTCH 6 • Checking the shape of BTR CAM ASSY: Is the BTR CAM ASSY bent or deformed? Replace the 2ND BTR CAM ASSY Go to step 7 7 • Checking the installation of 2ND BTR ASSY: Has the 2ND BTR ASSY been installed properly? Go to step 8 Reinstall the 2ND BTR ASSY 8 • Checking the installation of TRANSFER ASSY: Has the TRANFER ASSY been installed properly? Go to step 9 Reinstall the TRANSFER ASSY 9 • Replacing the MCU PWB and Performing Checks: Replace the MCU PWB. Is the problem solved? Problem solved Go to FIP-2.32 “Faulty LV/HV POWER SUPPLY”

• Code: 523
• Description: PCDC malfunction
• Remedy: 1 • Initial checking: Is there any parts of wrong specifications used, improper mounting, damage, distortion, dirt, or adherence of foreign matter? • Major parts to be checked: MCU PWB Replace or reinstall the relevant part. Go to step 2 2 • Checking whether the problem lies in engine or controller: Can a test print (single sheet / consecutive printing, about 10 sheets each) be performed normally with the engine alone? Check the Printer Controller. (If an error still occurs after replacing, go to step 3.)] Go to step 3 3 • Replacing the MCU PWB and Performing Checks: Replace the MCU PWB. Is the problem solved? Problem solved Go to FIP-2.33 “Noise”

• Code: 524
• Description: Toner density malfunction (Low density)
• Remedy: 1 • Initial checking: Is there any parts of wrong specifications used, improper mounting, damage, distortion, dirt, or adherence of foreign matter? • Major parts to be checked: DISPENSE MOTOR ASSY, DEVE. CONTACT PLATE ASSY Developer Assy, MAIN HARNESS ASSY, MCU PWB Replace or reinstall the relevant part. Go to step 2 2 • Checking whether the problem lies in engine or controller: Can a test print (single sheet / consecutive printing, about 10 sheets each) be performed normally with the engine alone? Check the Printer Controller. (If an error still occurs after replacing, go to step 3.)] Go to step 3 3 • Checking the Drum surface image: Are the various toner images developed properly on the Drum surface? • Turn the power OFF while you think there is an image being transferred in the course of printing, and visually inspect Cin50% patch on the Drum surface. Go to step 8 Go to step 4 4 • Checking the Drum surface picture image: Are all the colors of the various toner images on the Drum surface thin? • Turn the power OFF while you think there is an image being transferred in the course of printing, and visually inspect Cin50% patch on the Drum surface. Go to step 5 Go to step 11 5 • Checking the installation of Dispense Motor: Has the Dispense Motor been installed properly? • With the tool: Go to step 6 • Without the tool: Go to FIP-2.31 “Faulty the DISPENSE MOTOR ASSY” • If problem is not solved, go to step 7 Reinstall the DISPENSE MOTOR ASSY 6 • Checking the Dispense Motor: Does the Dispense Motor function properly? . By using the diagnostics commander, check by Digital Output Test device code "56". Go to step 7 Go to FIP-2.31 “Faulty the DISPENSE MOTOR ASSY” 7 • Checking the DEVE. CONTACT PLATE ASSY: Is the contact surface of the DEVE. CONTACT ASSY distorted? Or are there foreign matters on the contact surface of the DEVE. CONTACT ASSY? Replace the DEVE. CONTACT ASSY Go to step 8 8 • Checking the ADC Sensor surface: Is there dirt or any foreign matter adhering to the surface of the ADC Sensor? Remove dirt/ foreign matters. • With the tool: Go to step 9 • Without the tool: Go to FIP-2.16 “Faulty ADC Sensor” , FIP-2.17 “Faulty ADC Solenoid” 9 • Checking the ADC Sensor: Does the ADC Sensor function properly? . By using the diagnostics commander, check by Digital Output Test device code "72". Go to step 11 Go to FIP-2.16 “Faulty ADC Sensor” 10 • Checking the ADC Solenoid: Does the ADC Solenoid function properly? . By using the diagnostics commander, check by Digital Output Test device code "67". Go to step 11 Go to FIP-2.17 “Faulty ADC Solenoid” 11 • Replacing the Developer Assy and Performing Checks: Replace the Developer Assy with a new one for the color concerned. Does the problem still occur? Replace the MCU PWB-XL Problem solved

• Code: 525
• Description: Toner density malfunction (High density)
• Remedy: 1 • Initial checking: Is there any parts of wrong specifications used, improper mounting, damage, distortion, dirt, or adherence of foreign matter? • Major parts to be checked: DEVE.CONTACT PLATE ASSY, ADC SENSOR ASSY MCU PWB Replace or reinstall the relevant part. Go to step 2 2 • Checking whether the problem lies in engine or controller: Can a test print (single sheet / consecutive printing, about 10 sheets each) be performed normally with the engine alone? Check the Printer Controller. (If an error still occurs after replacing, go to step 3.)] Go to step 3 3 • Checking the DEVE. CONTACT PLATE ASSY Is the contact surface of the DEVE. CONTACT ASSY distorted? Or are there foreign matters on the contact surface of the DEVE. CONTACT ASSY? Replace the DEVE.CONTACT PLATE ASSY Go to step 4 4 • Checking the ADC Sensor surface: Is there dirt or any foreign matter adhering to the surface of the ADC Sensor? Remove dirt/foreign matters. • With the tool: Go to step 5 • Without the tool: Go to FIP-2.16 “Faulty ADC Sensor” FIP-2.17 “Faulty ADC Solenoid” 5 • Checking the ADC Sensor: Does the ADC Sensor function properly? . By using the diagnostics commander, check by Digital Output Test device code "72". Go to step 6 Go to FIP-2.16 “Faulty ADC Sensor” 6 • Checking the ADC Solenoid: Does the ADC Solenoid function properly? . By using the diagnostics commander, check by Digital Output Test device code "67". Go to step 7 Go to FIP-2.17 “Faulty ADC Solenoid” 7 • Replacing the MCU PWB and Performing Checks: Replace the MCU PWB. Is the problem solved? Problem solved Go to FIP-2.32 “Faulty LV/HV POWER SUPPLY”

• Code: 526
• Description: ADC sensor soiled
• Remedy: 1 • Initial checking: Is there any parts of wrong specifications used, improper mounting, damage, distortion, dirt, or adherence of foreign matter? • Major parts to be checked: ADC SENSOR ASSY, MAIN HARNESS ASSY MCU PWB Replace or reinstall the relevant part. Go to step 2 2 • Checking whether the problem lies in engine or controller: Can a test print (single sheet / consecutive printing, about 10 sheets each) be performed normally with the engine alone? Check the Printer Controller. (If an error still occurs after replacing, go to step 3.)] Go to step 3 3 • Checking the ADC Sensor surface: Is there dirt or any foreign matter adhering to the surface of the ADC Sensor? Remove dirt/foreign matters. • With the tool: Go to step 4 • Without the tool: Go to step 6 4 • Checking the ADC Sensor: Does the ADC Sensor function properly? . By using the diagnostics commander, check by Digital Output Test device code "72". Go to step 5 Go to FIP-2.16 “Faulty ADC Sensor” 5 • Checking the ADC Solenoid: Does the ADC Solenoid function properly? . By using the diagnostics commander, check by Digital Output Test device code "67". Go to step 7 Go to FIP-2.17 “Faulty ADC Solenoid” 6 • Checking the installation of ADC SENSOR ASSY: Has the ADC SENSOR ASSY been installed properly? Go to step 7 Reinstall the ADC SENSOR ASSY 7 • Replacing the MCU PWB and Performing Checks: Replace the MCU PWB. Is the problem solved? Problem solved Go to FIP-2.32 “Faulty LV/HV POWER SUPPLY”

• Code: 527
• Description: Deve home position sensor malfunction
• Remedy:

• Code: 530
• Description: Environment (humidity)sensor malfunction
• Remedy: 1 • Initial checking: Is there any parts of wrong specifications used, improper mounting, damage, distortion, dirt, or adherence of foreign matter? • Major parts to be checked: ENVIRONMENT SENSOR, P/H HARNESS ASSY, MCU PWB Replace or reinstall the relevant part. • With the tool: Go to step 2 or 3 • Without the tool: Go to step 4 or 5 2 • Checking the TEMP SENSOR: Does the TEMP SENSOR function properly? . By using the diagnostics commander, check by Analog Input Test device code "04". Go to step 6 Replace the ENVIRONMENT SENSOR 3 • Checking the Humidity SENSOR: Does the Humidity SENSOR function properly? . By using the diagnostics commander, check by Analog Input Test device code "06". Go to step 6 Replace the ENVIRONMENT SENSOR 4 • Checking the thermistor resistance of ENVIRONMENT SENSOR: Is the resistance between P/J105-1PIN . P/J105- 4PIN approx. 5 kO at room temperature (18~20°C)? Go to step 5 Replace the ENVIRONMENT SENSOR 5 • Checking the voltage of ENVIRONMENT SENSOR: Is the voltage between P/J23-5PIN . P/J23-4PIN on the MCU PWB in the range of about 0.1-4.0 VDC? Replace the MCU PWB-XL Replace the ENVIRONMENT SENSOR 6 • Checking for continuity of P/H HARNESS ASSY: Is there normal continuity between J23 . J105? Replace the MCU PWB-XL Replace the P/H HARNESS ASSY