HL-1850/1870N SERVICE MANUAL
5-9
5) Re-install the drum unit assembly into the printer. Close the front cover.
6) Plug in the power cord, and then turn on the power switch.
!
CAUTION:
•
Handle the drum unit carefully since it contains toner. If toner scatters and your hands or
cloths get dirty, immediately wipe or wash it off with cold water.
•
Do not touch the scanner window with your fingers.
•
Do not wipe the scanner window with isopropyl alcohol.
3.4
Cleaning the Electrical Terminals
To obtain the best print performance, be sure to clean the electrical terminals inside the printer
body.
1) Turn off the power switch and unplug the power cord.
2) Remove the drum unit from the printer.
3) Wipe the electrical terminals as shown in the figure below with a soft dry cloth.
Fig. 5-12
Summary of Contents for HL-1870N
Page 15: ...HL 1850 1870N SERVICE MANUAL xiii ...
Page 77: ...CHAPTER 2 INSTALLATION AND BASIC OPERATION 2 48 ...
Page 82: ...HL 1850 1870N SERVICE MANUAL 3 5 Fig 3 5 ...
Page 91: ...CHAPTER 3 THEORY OF OPERATION 3 14 Fig 3 15 ...
Page 101: ...CHAPTER 3 THEORY OF OPERATION 3 24 ...
Page 109: ...CHAPTER 4 DISASSEMBLY AND RE ASSEMBLY 4 2 ...
Page 131: ...CHAPTER 4 DISASSEMBLY AND RE ASSEMBLY 4 24 Fig 4 39 ...
Page 141: ...CHAPTER 4 DISASSEMBLY AND RE ASSEMBLY 4 34 Never touch the surface of the heat roller ...
Page 148: ...CHAPTER 4 DISASSEMBLY AND RE ASSEMBLY 4 41 ...
Page 158: ...CHAPTER 4 DISASSEMBLY AND RE ASSEMBLY 4 51 Fig 4 80 ...
Page 160: ...CHAPTER 4 DISASSEMBLY AND RE ASSEMBLY 4 53 Fig 4 82 ...
Page 167: ...CHAPTER 4 DISASSEMBLY AND RE ASSEMBLY 4 60 Fig 4 91 ...
Page 169: ...CHAPTER 4 DISASSEMBLY AND RE ASSEMBLY 4 62 Fig 4 93 ...
Page 172: ...CHAPTER 4 DISASSEMBLY AND RE ASSEMBLY 4 65 Fig 4 97 ...
Page 174: ...CHAPTER 4 DISASSEMBLY AND RE ASSEMBLY 4 67 3 27 Harness Winding Form ...
Page 183: ...CHAPTER 5 PERIODIC MAINTENANCE 5 8 ...
Page 186: ...HL 1850 1870N SERVICE MANUAL 5 11 ...
Page 194: ...CHAPTER 6 TROUBLESHOOTING 6 8 error in this chapter ...
Page 202: ...CHAPTER 6 TROUBLESHOOTING 6 16 ...
Page 205: ...HL 1850 1870N SERVICE MANUAL 6 19 ...
Page 210: ...CHAPTER 6 TROUBLESHOOTING 6 24 ...
Page 237: ...HL 1850 1870N SERVICE MANUAL 6 51 No Refer and compare with I 15 ...
Page 255: ...HL 1850 1870N SERVICE MANUAL 6 69 ...
Page 261: ...CHAPTER 7 HIDDEN FUNCTIONS 7 6 DRAM CHECK START START DRAM TEST Tests DRAM data ...
Page 270: ...HL 1850 1870N SERVICE MANUAL 7 15 ...
Page 271: ......
Page 272: ...Appendix 1 Connection Diagram HL 1850 1870N A 1 ...
Page 273: ...Appendix 2 Main PCB Circuit Diagram HL 1850 1870N 1 6 CODE LJ8453001 B512078CIR 1 6 A 2 NAME ...
Page 274: ...Appendix 3 Main PCB Circuit Diagram HL 1850 1870N 2 6 CODE LJ8453001 B512078CIR 2 6 A 3 NAME ...
Page 275: ...Appendix 4 Main PCB Circuit Diagram HL 1850 1870N 3 6 CODE LJ8453001 B512078CIR 3 6 A 4 NAME ...
Page 276: ...Appendix 5 Main PCB Circuit Diagram HL 1850 1870N 4 6 CODE LJ8453001 B512078CIR 4 6 A 5 NAME ...
Page 277: ...Appendix 6 Main PCB Circuit Diagram HL 1850 1870N 5 6 CODE LJ8453001 B512078CIR 5 6 A 6 NAME ...
Page 278: ...Appendix 7 Main PCB Circuit Diagram HL 1850 1870N 6 6 CODE LJ8453001 B512078CIR 6 6 A 7 NAME ...
Page 284: ...Appendix 13 High voltage Power Supply PCB Circuit Diagram A 13 NAME High voltage PS Circuit ...
Page 303: ...APPENDIX A 32 ...