Muratec MFX-C4000 Field Engineering Manual page 188

Problem Description
Horizontal Dark
Band (1.8~2.1mm)
on All Images
Horizontal Periodic
Micro Jitter (sub-
1mm Pitch) for a
Particular Color
Horizontal Periodic
Jitter (2~3mm Pitch)
for YMC Color
Vertical White Band
Vertical Moving
White Band
Service Manual
Alignment & Troubleshooting
Cause Description
1. Runout on Auger in
Developing Unit
1. Unbalanced
Charging Bias
1. High Torque loaded
on Waste Auger in
Developing Unit
1. ontaminations on
LSU Outer Window
2. Partially No
Developer on
Developing Roller
3. Vertical Damage on
ITB
1. Contaminations on
Doctor Blade Gap
Action to Resolve
[1. Runout on Auger in Developing Unit]
1.1) The problem occurs because of increasing the drive load in
Developing unit.
1.2) Check the OPC curve drive torque. If the drive torque is
increased, check the waste toner overflow of the OPC unit.
If it is overflowed, replace the developing unit.
[1. Unbalanced Charging Bias]
1.1) It is occurs because of the unbalanced Charging Bias.
Check the external temparature sensor and the humidity
sensor.
1.3) Check the Charge Bias [TM #105-0010~0016]. If there is
any wrong problem, change the value.
1.4) Check the Charge Bias [EDC #105-0000~003].
1.5) If the charge bias is defective, replace the HVPS.
1.6) If the charge bias is OK, replace the Developing unit.
[1. High Torque loaded on Waste Auger in Developing Unit]
1.1) The problem occurs because of increasing the drive load in
Developing unit.
1.2) Check the OPC curve drive torque. If the drive torque is
increased, check the waste toner overflow of the OPC unit.
If it is overflowed, replace the developing unit.
1.3) Check the dirve torque in Deve Roller curve.
If the drive torque of the Deve Roller is increased, shake
the developing unit horizontally and re-install it. If the
problem persists, replace the developing unit because of
the gear part.
[1. Contaminations on LSU Outer Window]
1.1) Check that the LSU windows is contaminated by dirt
1.2) Check that there is the contamination on the optical path of
the developing unit.
[2. Partially No Developer on Developing Roller]
2.1) Check that there is the dirt between Deve roller and Dr.
Blade in Developing unit.
[3. Vertical Damage on ITB]
3.1) If the surface of ITB gets damaged, replace the ITB.
[1. Contaminations on Doctor Blade Gap]
1.1) Check that there are the dirt or contaminations between
Deve roller and Dr. Blade in Developing unit.
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