Vertical fine lines appears on gray background

Issue description

When printing a document with gray background, vertical fine lines appear.

• Sample print quality defect 1
• Sample print quality defect 2

Solution

1. Check if toner cartridge is a genuine Lexmark toner cartridge. See Genuine Verification.

   Is the toner cartridge genuine?

   • If Yes, proceed to the next step.
   • If No, Cartridge may be the problem. Recommend that the customer return to point of purchase and explain Lexmark's support statement regarding the use of third-party supplies.


2. Turn OFF Quiet Mode if it is turned ON or change Print Resolution so that is not set to 1200 dpi.

   Issue resolved?

   • If Yes, provide the explanation that running at slow speeds increases the probability of this print quality issue.
   • If No, proceed to the next step.


3. Ask the customer if the printer has been printing continuously within the past hour?

   Issue resolved?

   • If Yes, Leave the printer ON, but allow it to rest for 15-30 minute. If the issue is fixed, then explain that extreme or short bursts of heavy use can also increase the probability of this print quality issue.

   Note:  Please make sure not to turn off the printer because some of the important data used in the EP algorithms gets reset at POR.

   • If No, proceed to the next step.


4. Configure EngineSetting 9 = 4, by going to Engine Settings in under the diagnostics menu. To access the Diagnostics Menu press * + * + 3 + 6.

   Issue resolved?

   • If Yes, this will disable the algorithm that is the significant contributor to this print issue, but it may have an impact on other PQ issues such as light vertical streaks.
   • If No, contact the next level of support for further troubleshooting.