Konica-Minolta bizhub 4752

Printer: uneven density in main scan direction

Troubleshooting procedure

Step	Section	Check item	Result	Action
1	Imaging unit	The surface of the PC drum is scratched.	YES	Replace the imaging unit.
2		Dirty on the outside.	YES	Clean.
3	Transfer roller	Check that the spring does not come off during the pressure operation of the transfer roller.	NO	Correct.
				Replace the transfer roller.
4		The problem has been eliminated through the checks of steps up to 3.	NO	Replace the printhead.
				Replace the power supply unit.

Printer: low image density

Troubleshooting procedure

Step	Section	Check item	Result	Action
1	Toner density sensor	The surface of the toner density sensor is dirty.	YES	Clean.
2	Transfer roller	Check that the spring does not come off during the pressure operation of the transfer roller.	NO	Correct.
				Replace the transfer roller.
3		The problem has been eliminated through the checks of steps up to 2.	NO	Replace the imaging unit.
				Replace the toner density sensor.
				Replace the power supply unit.
				Replace the printhead.
				Replace the MFP board.

Printer: gradation reproduction failure

Troubleshooting procedure

Step	Section	Check item	Result	Action
1	Photo/density	Original type and screen pattern are selected properly.	NO	Change screen pattern.
2		The problem has been eliminated through the checks of steps up to 1.	NO	Replace the imaging unit.
				Replace the power supply unit.
				Replace the printhead.
				Replace the MFP board.