Muratec MFX-C4000 Field Engineering Manual page 191

Problem Description
White Spot on Solid
Image
(continue..)
Dot Size Black/Color
Spots
Offset Image (after-
image on OPC)
Service Manual
Alignment & Troubleshooting
Cause Description
1. Unstable T2 Transfer
Roller Nip
2. High T2 Transfer
Voltage
(continue..)
1. Developer Leakage
2. Unstable Charging
Bias
1. Poor Erasing
2. Poor Mechanical
Cleaning
Action to Resolve
[2. High T2 Transfer Voltage]
2.1) Check the T2 transfer voltage [TM #107-0008~0009]. If
there is any wrong value, change the value.[TM #107-
0008~0009].
2.2) Check the T2 Bias Read [EDC #107-0005]. If it is defective,
replace the HVPS.
2.3) Check the ITB Drive Roller Ground. If it is defective, replace
the ITB.
[1. Developer Leakage]
1.1) The problem occurs because of the developer leakage.
1.2) Shake the developer horizontally and re-install it.
1.3) If the problem persists, print the 5~10 pages of the Full
Solide image. And print the 5 pages of temporary image. Is
the problem dieappeared?
1.4) Try these steps for 2,3 times. If the problem is not solved,
replace the developing unit.
[2. Unstable Charging Bias]
2.1) Check the external temparature sensor and humidity
sensor.
2.2) If the sensor is normal, check the Charge Bias[TM #105-
0010~0016]. If or not, change the value.
2.3) Check the Charge Bias [EDC #105-0000~003]. If it is
defective, replace the HVPS.
2.4) If it is normal, check the contact between charge high
voltage harness and developing unit.
2.5) If it is normal, check the OPC grounding.
[1. Poor Erasing]
1.1) Check the Eraser Lamp working for each color.
1.2) If the Eraser lamp is normal, check that the Eraser Lens is
contaminated or not.
1.3) If the Eraser Lens is normal, check the OPC surface. If
the OPC rotates more than OPC life, the OPC coating
thickness will be thin.
[2. Poor Mechanical Cleaning]
2.1) When the OPC rotates, check the Cleaning Blade is
working normally.
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