Konica Minolta BIZHUB 25E Field Engineering Manual page 228

4.5.3 Black image
Scanner section
Section Step Check item
Scanner section 1
2
3
4
5
Printer section
Section Step Check item
Drum cartridge 1
Circuit boards 2
3
Does lamp turn ON when making
copy with open platen cover?
Do step 1 again.
Does the voltage level of pin1-3
of P8A on the main control panel
change to +3.3V?
Is the CIS installed properly?
Is the CIS lens dirty?
Is the trouble settled with above
steps?
Are the grid bias, charge bias and
drum ground contact terminal dirty or
deformed?
Are the connections from LED print
head and from high-voltage board to
main control board in good condition?
(Check plugs firmly plugged and
snapped harness.)
Is the trouble settled with above
steps?
Result Remedy
Yes Check step 4 and onward
No Reconnect / Replace harness
No Replace main control board.
No Install it properly
Yes Clean, or replace the part and
adjust the background level
No 1. Adjust the background level.
2. Replace CIS.
3. Replace main control board.
Result Remedy
Yes Clean / Repair
No Reconnect / Replace harness
No 1. Replace drum cartridge.
2. Replace LED print head.
3. Replace main control board.
4. Replace high-voltage power
board.
4-22