CHAPTER 6 TROUBLESHOOTING
6-42
I-7
Black and blurred horizontal stripes
Possible cause
Step
Check
Result
Remedy
Ground
contacts
Scratch on the
drum
1
Are the horizontal stripes at
94mm (photosensitive drum)
intervals?
Yes
The photosensitive
drum was scratched.
Replace the drum
unit.
Toner stuck on
the developer
roller
2
Are the horizontal stripes at
39mm (developer roller)
intervals?
Yes
After printing several
pages, the problem
will disappear.
If not, replace the
toner cartridge.
Scratch on the
heat roller
3
Are the horizontal stripes at
79mm (heat roller) intervals?
Yes
Replace the heat
roller.
Corona contact
failure
4
Are the charge electrodes
between the printer body and
the drum unit dirty?
Yes
Clean both electrodes.
(3)
High-voltage
power supply
PCB failure
5
Is the problem solved after
replacing the high-voltage
power supply PCB?
Yes
Replace the high-
voltage power supply
PCB.
I-8
Black vertical streaks (in a gray background)
Possible cause
Step
Check
Result
Remedy
Ground
contacts
Translucent
stain on the
scanner window
1
Is there any dirt on the scanner
window?
Yes
1) Clean the scanner
window.
2) If it is not effective,
replace the laser
unit.
Corona failure
2
Is the corona wire dirty?
Yes
Clean the corona wire
with the wire cleaner.
(2)
User Check
(1) The drum unit may be damaged. Install a new drum unit.
(2) Check the paper used meets the recommended paper specifications.
(3) Clean the printer interior and the corona wire in the drum unit.
Содержание HL-1870N
Страница 15: ...HL 1850 1870N SERVICE MANUAL xiii ...
Страница 77: ...CHAPTER 2 INSTALLATION AND BASIC OPERATION 2 48 ...
Страница 82: ...HL 1850 1870N SERVICE MANUAL 3 5 Fig 3 5 ...
Страница 83: ...CHAPTER 3 THEORY OF OPERATION 3 6 1 3 2 ROM Two 64 Mbits ROMs x 16 bit are fitted Fig 3 6 HL 1850 HL 1870N ...
Страница 85: ...CHAPTER 3 THEORY OF OPERATION 3 8 1 3 4 SDRAM A 64M bit SDRAM x 32 bits is used as the RAM Fig 3 8 HL 1850 ...
Страница 86: ...HL 1850 1870N SERVICE MANUAL 3 9 Two 64M bit SDRAMs x 16 bits are used as the RAM Fig 3 9 HL 1870N ...
Страница 91: ...CHAPTER 3 THEORY OF OPERATION 3 14 Fig 3 15 ...
Страница 101: ...CHAPTER 3 THEORY OF OPERATION 3 24 ...
Страница 109: ...CHAPTER 4 DISASSEMBLY AND RE ASSEMBLY 4 2 ...
Страница 131: ...CHAPTER 4 DISASSEMBLY AND RE ASSEMBLY 4 24 Fig 4 39 ...
Страница 141: ...CHAPTER 4 DISASSEMBLY AND RE ASSEMBLY 4 34 Never touch the surface of the heat roller ...
Страница 148: ...CHAPTER 4 DISASSEMBLY AND RE ASSEMBLY 4 41 ...
Страница 158: ...CHAPTER 4 DISASSEMBLY AND RE ASSEMBLY 4 51 Fig 4 80 ...
Страница 160: ...CHAPTER 4 DISASSEMBLY AND RE ASSEMBLY 4 53 Fig 4 82 ...
Страница 167: ...CHAPTER 4 DISASSEMBLY AND RE ASSEMBLY 4 60 Fig 4 91 ...
Страница 169: ...CHAPTER 4 DISASSEMBLY AND RE ASSEMBLY 4 62 Fig 4 93 ...
Страница 172: ...CHAPTER 4 DISASSEMBLY AND RE ASSEMBLY 4 65 Fig 4 97 ...
Страница 174: ...CHAPTER 4 DISASSEMBLY AND RE ASSEMBLY 4 67 3 27 Harness Winding Form ...
Страница 183: ...CHAPTER 5 PERIODIC MAINTENANCE 5 8 ...
Страница 186: ...HL 1850 1870N SERVICE MANUAL 5 11 ...
Страница 194: ...CHAPTER 6 TROUBLESHOOTING 6 8 error in this chapter ...
Страница 202: ...CHAPTER 6 TROUBLESHOOTING 6 16 ...
Страница 205: ...HL 1850 1870N SERVICE MANUAL 6 19 ...
Страница 210: ...CHAPTER 6 TROUBLESHOOTING 6 24 ...
Страница 237: ...HL 1850 1870N SERVICE MANUAL 6 51 No Refer and compare with I 15 ...
Страница 255: ...HL 1850 1870N SERVICE MANUAL 6 69 ...
Страница 261: ...CHAPTER 7 HIDDEN FUNCTIONS 7 6 DRAM CHECK START START DRAM TEST Tests DRAM data ...
Страница 270: ...HL 1850 1870N SERVICE MANUAL 7 15 ...
Страница 271: ......
Страница 272: ...Appendix 1 Connection Diagram HL 1850 1870N A 1 ...
Страница 273: ...Appendix 2 Main PCB Circuit Diagram HL 1850 1870N 1 6 CODE LJ8453001 B512078CIR 1 6 A 2 NAME ...
Страница 274: ...Appendix 3 Main PCB Circuit Diagram HL 1850 1870N 2 6 CODE LJ8453001 B512078CIR 2 6 A 3 NAME ...
Страница 275: ...Appendix 4 Main PCB Circuit Diagram HL 1850 1870N 3 6 CODE LJ8453001 B512078CIR 3 6 A 4 NAME ...
Страница 276: ...Appendix 5 Main PCB Circuit Diagram HL 1850 1870N 4 6 CODE LJ8453001 B512078CIR 4 6 A 5 NAME ...
Страница 277: ...Appendix 6 Main PCB Circuit Diagram HL 1850 1870N 5 6 CODE LJ8453001 B512078CIR 5 6 A 6 NAME ...
Страница 278: ...Appendix 7 Main PCB Circuit Diagram HL 1850 1870N 6 6 CODE LJ8453001 B512078CIR 6 6 A 7 NAME ...
Страница 281: ...Appendix 10 Network Board PCB Circuit Diagram HL 1850 1870N CODE LJ8439001 A 10 NAME B512058CIR ...
Страница 282: ...Appendix 11 Low voltage Power Supply PCB Circuit Diagram 100V A 11 NAME Low voltage PS Circuit 100V ...
Страница 283: ...Appendix 12 Low voltage Power Supply PCB Circuit Diagram 200V A 12 NAME Low voltage PS Circuit 200V ...
Страница 284: ...Appendix 13 High voltage Power Supply PCB Circuit Diagram A 13 NAME High voltage PS Circuit ...
Страница 303: ...APPENDIX A 32 ...