Ricoh M126 - Black Page

Service Checks
SM 6-73 M126/M127/M128
Trouble-
shooting
Black page
 Incorrect laser exposure or incorrect charging of the photoconductor causes an all black
page. Always verify the same results from a different print cartridge assembly and
developer before proceeding.
FRU Action
Toner electrodes
(not a FRU)
Check the three rearward electrodes below the toner cartridge
assembly for contamination, damage, or a short to ground.
Correct as necessary.
Check continuity between the cable (DEV, TAR, and doctor blade)
connection PCN3 and on the contact tips below the toner cartridge
assembly.
 If continuity fails, then call the next level of service.
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 verify +24Vdc on pins 17 and 19 of the
cable.
Verify +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.