Lexmark 632n - T B/W Laser Printer Service Manual page 113

4060-xxx
Print quality—random marks
Service tip: The primary cause of random marks is due to loose material moving around inside the
printer and attaching to the photoconductor, charge roll, or transfer roll.
Symptom
1 Random marks
Print quality—blurred or fuzzy print
Blurred of fuzzy print is usually caused by a problem in the main drive gearbox assembly, alignment
assembly, any feed roller, or in the transfer roll bearings or transfer roll. Check the gearbox assembly
for correct operation. Check the transfer roll for binds or a contaminated shaft or bearings.
Blurred print can also be caused by incorrect feeding from one of the input paper sources, paper
trays, duplex option, or envelope feeder.
Check the high voltage contacts to ensure they are not bent, corroded, or damaged. Replace as
necessary.
Print quality—evenly spaced horizontal lines or marks
FRU
1 Lines spaced 3.19 mm
(.126 inch) apart
2 Lines spaced 22.32
mm(.882 inch) apart
Lines spaced 28.7 mm
(1.130 inch) apart
Lines spaced 47.83 mm
(1.883 inch) apart
Lines spaced 63.77 mm
(2.511 inch) apart
3 Lines spaced 38.26 mm
(1.506 inch) apart
4 Lines spaced 44.64 mm
(1.757 inch) apart
5
Lines spaced 47.19 mm
(1.858 inch) apart
6 Lines spaced 49.16 mm
(1.935 inch) apart
2-80
Service Manual
Action
Check the print cartridge for loose or foreign material that might be
on the photoconductor. Check the transfer roll and charge roll for any
pieces of material that are stuck to the rolls.
Action
This can be caused by the motor pinion gear on the main drive motor.
Replace the main drive motor.
This can be caused by a defective gear in the main drive gearbox
assembly. Replace the main drive gearbox assembly.
This can be caused by defective gear(s) in the main drive gearbox.
Replace the FRUs in the following order:
• Main drive gearbox
• Reference edge
Replace the FRUs in the following order:
• Developer drive assembly
• Main drive gearbox assembly
Replace the FRUs in the following order:
• Toner cartridge
• Charge roll
• Developer drive assembly
Replace the toner cartridge.