Printronix L1024, Maintenance Manual

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13–8 Chapter 13 – Troubleshooting Guide
Detailed Troubleshooting Steps
By following these steps, you will be able to pinpoint the source of the problem and make any necessary
corrections needed to fix the problem.
100. Horizontal Image Errors
110. Uniform 1 inch interval line (indistinct width and fuzzy edges).
This is best exhibited by printing a black page.
111. The contact between the developer sleeve and the electrode is defective.
a. Apply conductive grease to the developer sleeve contact.
b. Replace the developer unit.
112. The contact between the developer unit and the H.V.P.S. electrode or spring is defective.
a. Make sure there is no corrosion on the spring of the H.V.P.S. contact or on the
developer unit contact.
b. Make sure the spring is making good physical contact with the contact. The spring can
be lengthened by pulling it in order to make better contact. Make sure to pull the spring
upward, not at an angle.
113. The bias voltage from the H.V.P.S. is incorrect.
a. Check the developer roller bias via the procedure in Chapter 8, Power Supplies, and
adjust if needed.
b. Replace the H.V.P.S. if the bias cannot be correctly adjusted.
120. Black horizontal line (thin with sharp edges).
This is usually caused by a static discharge to the laser. This may be present on a blank
page.
121. The ground connection between the paper brush and the printer is faulty. The paper
brush builds a static charge that discharges into the laser drive circuitry through the
printer base pan.
a. Remove the paper brush and check to see if the line is still present when printing.
b. Make sure the paper brush is properly seated.
c. Make sure the grounding spring on the paper brush is not damaged or corroded.
d. Make sure the grounding spring is making good physical contact with the shafts of the
paper brushes.
e. Replace the paper brush if the above steps do not fix the problem, or if the line is not
present in step a.
122. The contact between the transfer charger electrode and the H.V.P.S. contact spring is
faulty. This causes discharges (sparks) which cause the laser drive circuitry to turn on the
laser when it should not be on.