FRU
Action
LVPS/HVPS board
Controller board
Miscellaneous cables
With the machine off, disconnect the LVPS/HVPS cable from J502 on the
engine board.
Turn the machine on, and 24Vdc on pins 17 and 19 of the cable.
5 V dc on pins 1, 3-5, 11, 13, and 15.
Verify ground on pins 10, 12,14, 16, and 18.
• If any of the values are incorrect, then replace LVPS/HVPS board.
• If the grounds are incorrect, then check ground paths.
• Check continuity in the cable. If the cable is bad, then call the next
level of support.
• If the values are correct and the toner electrodes are good, then
replace the controller board.
• See “LVPS/HVPS Service Check” and “Engine Board Service Check”
in “Troubleshooting”, if necessary.
Heavy background
Poor development or poorly charged toner particles cause excessive background. This is more
noticeable as the toner cartridge nears end-of-life.
FRU
Action
Toner cartridge (not a
FRU)
PC Kit (not a FRU)
Check the toner darkness setting in the driver. Try a lower setting.
Make sure the toner cartridge and PC Kit are correctly installed and the
high voltage contacts are clean.
If the toner cartridge and PC Kit are installed correctly, then try a new PC Kit
first and then toner cartridge.
LVPS/HVPS
Engine board
Check the contacts for correct installation and contamination where contact
is made between the print cartridge assembly and spring contacts which
connect to the LVPS/HVPS board at CN203. Clean as necessary.
If this does not correct the problem, then replace the following FRUs one at
a time in the order shown:
• LVPS/HVPS board. See “Black page” in “Troubleshooting” for pin
values.
• Engine board
6. Troubleshooting
254
6
Summary of Contents for LI-MF1 M126
Page 1: ...Model LI MF1 Machine Codes M126 M127 M128 Field Service Manual 26 August 2011 ...
Page 2: ......
Page 3: ...Safety Notices The following laser notice labels may be attached to this machine 1 ...
Page 4: ...2 ...
Page 5: ...3 ...
Page 6: ...4 ...
Page 7: ...5 ...
Page 8: ...6 ...
Page 9: ...7 ...
Page 10: ...8 ...
Page 17: ...XPS XML Paper Specification 15 ...
Page 29: ...M Auto compensator Overview 27 1 ...
Page 30: ...Main Boards Controller Board 1 Product Information 28 1 ...
Page 37: ...2 Installation Installation Refer to the User s Guide 35 2 ...
Page 38: ...2 Installation 36 2 ...
Page 51: ...2 Remove the three screws B securing the top of the controller shield Removal Procedures 49 4 ...
Page 59: ...6 Remove the screw D from the gear E 7 Remove the plastic bushing F Removal Procedures 57 4 ...
Page 142: ...4 Replacement and Adjustment 140 4 ...
Page 192: ...5 System Maintenance 190 5 ...
Page 198: ...Symptom Action Fax reception fails p 276 Fax Reception Service Check 6 Troubleshooting 196 6 ...
Page 298: ...6 Troubleshooting 296 6 ...
Page 302: ...7 Energy Saving 300 7 ...
Page 303: ...Model LI MF1 Machine Codes M126 M127 M128 Appendices 12 October 2011 ...
Page 304: ......
Page 306: ...2 ...
Page 322: ...1 Appendix Specifications 18 1 ...
Page 324: ...MEMO 20 EN ...