Printronix L1024, Maintenance Manual

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13–23 Chapter 13 – Troubleshooting Guide
a. The paper is not feeding freely into the printer. Make sure there is nothing binding the
paper as it enter or exits the printer.
b. The electric clutch is slipping and must be replaced.
622. As well as a compressed image, the printer exhibits more noise than during normal
operation.
a. The drive belt is damaged or missing a tooth. Replace the belt.
b. The spring on the belt tensioner is weak or stretched and must be replaced. This
results in the drive belt slipping on the fuser pulley.
c. The drive belt pulley on the fuser is damaged and must be replaced.
d. The stepper motor is not functioning properly. Replace the stepper motor.
e. The stepper motor drive circuitry in the L.V.P.S. is faulty. Replace the L.V.P.S.
630. Ghost or mirror image.
631. The density setting on the H.V.P.S. is too high.
a. The green density knob on the H.V.P.S. is set too high, resulting in too much toner
being deposited on the OPC drum.
There is more toner on the drum than can be transferred to the paper, which results in excess
toner being left on the drum. The OPC drum cleaning system cannot handle the excess toner,
and some of it is left on the drum after the cleaning process. This residual toner is then
deposited on the paper during the transfer process, during the next rotation of the drum.
632. The erase LEDs are not discharging the OPC drum sufficiently.
a. Inspect the LED assembly, looking for broken or blocked LEDs.
Toner is deposited occasionally on one of the LEDs. The LEDs can be checked by opening the
printer cover, defeating the cover open switch, and turning on the printer. The LEDs will
illuminate during the power-on sequence.
b. The LEDs are not being turned on by the Engine Controller Board. Replace the Engine
Controller Board.
c. The LED wires are damaged in the LSU cable. Replace the cable.
d. The connections for LEDs inside the LSU are faulty. Replace the LSU.
633. The OPC drum cleaning voltage from the H.V.P.S. is not correct. It is either too low or not
present.
a. Make sure the H.V.P.S. contact springs and the OPC drum unit contacts are clean of
toner and are corrosion free. If compressed, the springs can be lengthened by pulling.
Make sure to pull the spring upward, not at an angle.
b. Check the cleaning voltages according to the procedure in Chapter 8, Power Supplies.
c. Replace the H.V.P.S. if the correct voltage cannot be obtained.
634. The OPC drum is worn out or has excessive toner buildup. This usually occurs after the
drum count has exceeded 30,000 pages. If the count is this high, the drum should be
replaced as its life has been exceeded.