Xerox WorkCentre Pro 423 Service Manual page 264

WorkCentre Pro 423/428
Smear Copy sample
C - 15
Symptom: Smear (Copies with blurred images)
• Smear represents blurred images caused by vibration or speed changes of Drum and paper
in the transfer process.
• Check paper transport drive mechanism, mainly drum and paper feed when smear problem
occurs.
Cause
Faulty DTS
Fuser
• Foreign matter or damage of
Heat Roller Gears
Fuser
• Deformed Pressure Roller
Damage of Paper Transport Gear,
Pulley or Belt
Faulty rotation of Drum
Faulty Main Drive Assy
Foreign matter in Transfer area
R/H Chute
• R/H Chute is loose/detached or
binding.
BTR feed fault
• BTR is dirty.
j0hn3018
Corrective action
• Replace DTS.
• Clean or replace the Gears.
• Replace Pressure Roller.
• Replace them.
• Check CRU Coupling.
• Replace CRU.
• Replace Main Drive Assy.
• Remove foreign matter.
• Repair/Replace the Chute.
•
Replace BTR.
3-20 CHAPTER 3 IMAGE QUALITY TROUBLESHOOTING
Jitter/Data error Copy sample
C - 16
Symptom: Jitter/Data error (Zigzag lines in copy feed direction)
• FAX receive:
Jitter or data error of receive data
• Copy mode: Jitter of print data
Cause
Jitter/data error during Fax receive
• Data error caused by noise of
telephone line
Jitter/data error during Fax receive
• Jitter/data error caused by poor
electrical connection of NCU
Jitter/data error during Fax receive
• Faulty modem in MF MAIN
PWB
Jitter in copy mode
• Faulty MCU/SW PWB or
IIT/IPS PWB
Jitter in copy mode
• Faulty SOS sensor or ROS
Drive PWB (Occurs at the
same level in the inside and
outside.)
Jitter in copy mode
• Faulty ROS Motor
3.3 Image Quality Troubleshooting
j0hn3019
Corrective action
• Print out built-in Test Pattern to check and isolate
faulty board.
• Check NCU PWB for poor electrical connection.
(BSD 19.2)
• Replace MF MAIN PWB. (PL 7.3)
• Print out built-in Test Pattern to check and isolate
faulty board.
• Replace ROS Assy.
• Replace ROS Assy.
• Replace MCU/SW PWB.