Image Is Too Light; Background Is Visible; A White Line Appears Longitudinally - Kyocera TASKalfa 620 Service Manual

(3) Image is too light.

Copy example
Insufficient toner.
Deteriorated toner.
The transfer
voltage is
not output
properly.
Defective
developing
bias output.
Surface
potential is
high.

(4) Background is visible.

Copy example
Deteriorated toner.
Dirty main charger wire.

(5) A white line appears longitudinally.

Copy example
Foreign matter in the developing unit.
Flawed drum.
Dirty shading plate.
Dirty DP separation roller.
Foreign matter in the laser scanner
unit.
Dirty CIS or CIS roller.
Causes
The connector terminals
of the transfer high volt-
age PWB make poor
contact.
Poor insertion transfer
unit.
Continuity malfunction
inside the transfer belt.
Defective engine PWB.
Poor installation of high
voltage PWB.
Defective high voltage
PWB.
Causes
Causes
Check procedures/corrective measures
If the display shows the message requesting toner replen-
ishment, replace the toner container.
Perform the drum refresh operation (see page 1-3-105).
Reinsert the connector. Also check for continuity within the
connector cable. If none, remedy or replace the cable.
Reinstall the transfer unit.
Check for continuity. If none, remedy or replace.
Check if YC7-5 both or one side of YC7-6 on the engine
PWB go low when run maintenance item U101. If not,
replace the engine PWB.
Check if 5 V DC is output from YC7-3 on the engine PWB
when run maintenance item U101. If not, replace the
engine PWB.
Check the installation state of the high voltage PWB.
If the grit output is zero when the high voltage PWB is
installed securely, replace the high voltage PWB.
Check procedures/corrective measures
Perform the drum refresh operation (see page 1-3-105).
Clean the wire or, if it is extremely dirty, replace it.
Check procedures/corrective measures
Check if the magnetic brush is formed uniformly. If not,
replace the developer.
Replace the drum (see page 1-5-44).
Clean the shading plate.
Clean the DP separation roller.
Replace the laser scanner unit (see page 1-5-36).
Clean the CIS or CIS roller.
2KN/2KP
1-4-53