Samsung ML-920 Service Manual page 5

Contents
4. Maintenance & Troubleshooting ................................................. page(4-1)
4-1 Preventative Maintenance .................................................................................. page(4-1)
4-2 Error Messages.................................................................................................. page(4-2)
4-3 User Mode.......................................................................................................... page(4-4)
4-4 Tech Mode.......................................................................................................... page(4-5)
4-4-1 How to Enter Service Mode .......................................................................... page(4-5)
4-4-2 Setting-up System in Tech Mode .................................................................. page(4-6)
4-4-3 SYSTEM DATA.............................................................................................. page(4-7)
4-4-4 MEMORY CLEAR ......................................................................................... page(4-7)
4-4-5 MAINTENANCE ............................................................................................ page(4-8)
4-4-6 REPORT/HELP............................................................................................. page(4-11)
4-4-7 Firmware Upgrade ........................................................................................ page(4-12)
4-4-7-1 Local Machine......................................................................................... page(4-12)
4-4-7-2 Remote FAX............................................................................................. page(4-12)
4-5 Identify Sale Date............................................................................................... page(4-13)
4-6 ENGINE TEST MODE........................................................................................ page(4-14)
4-6-1 To enter the Engine Test Mode...................................................................... page(4-14)
4-6-2 Diagnostc ...................................................................................................... page(4-14)
4-6-3 ENGINE PRINT ............................................................................................ page(4-14)
4-7 Troubleshooting .................................................................................................. page(4-15)
4-7-1 Print Quality ................................................................................................. page(4-15)
• Abnormal Image Printing and Defective Roller ................................................................. page(4-17)
• No Image ..........................................................................................................................page(4-18)
• All Black ............................................................................................................................page(4-20)
• Vertical White Line (Band).................................................................................................page(4-21)
• Dark Image .......................................................................................................................page(4-22)
• Background.......................................................................................................................page(4-23)
• Ghost ................................................................................................................................page(4-24
• Black Dot..........................................................................................................................page(4-25)
• Horizontal Band ................................................................................................................page(4-26)
• Irregular Density................................................................................................................page(4-27)
• White Spot ........................................................................................................................page(4-28)
• Trembling at the End When OHP Printing ......................................................................... page(4-29)
• Poor Fusing Grade............................................................................................................page(4-30)
4-7-2 Malfunction................................................................................................... page(4-31)
• No Power (LCD NO display LED Off)................................................................................ page(4-33)
• Fuser Error........................................................................................................................page(4-34)
• Paper Jam (Mis-Feeding).................................................................................................page(4-35)
• Paper Jam(Jam 1).............................................................................................................page(4-36)
• Engine Error......................................................................................................................page(4-37)
4-7-3 Toner Cartridge and Drum Cartridge Service .............................................. page(4-38)
4-7-3-1 Signs and Measures at Poor toner cartridge .......................................... page(4-39)
4-7-4 The cause and solutions of bad environment of the software ...................... page(4-42)
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