Lexmark 5028-135 CS720

Performing the initial troubleshooting check

• With the power cord unplugged from the electrical outlet, check if the cord is free from breakage, short circuits, disconnected wires, or incorrect connections.
• Make sure that the printer is properly grounded. . Make sure that the power supply line voltage is within 10% of the rated line voltage.
• Make sure that the printer is securely installed on a level surface in a well.ventilated area.
• Make sure that the temperature and relative humidity are within the specifications. See "Temperature informationh".
• Avoid locations that:
  – Generate ammonia gas
  – Are exposed to direct sunlight
  – Are near open flames
  – Are dusty
• Make sure that the recommended paper for this printer is used.
• Do a test print with paper from a newly opened package, and then check the result.

Power-on reset (POR) sequence

When you turn on the printer, it performs a POR sequence.
Check for the correct POR function of the printer by observing the following:

1. The initial boot screen appears.
2. The splash screen appears.
3. The progress bar appears on the splash screen.
4. The printer begins to POST, and the motors and sensors are polled and tested.
5. Scanner calibration starts.
6. The home screen displays.
7. Printer calibration may begin.
   Note: If any of the tests fail, the printer displays an error code.

Initial print quality check

Before troubleshooting print problems, perform the following:

• Make sure that the printer is located in an area that follows the recommended operating environment and power requirement specifications.
• Check the status of supplies. Replace supplies that are low or empty.
• Load 20.lb plain letter or A4 paper. Make sure that the paper guides are properly set and locked. From the control panel, set the paper size and type to match the paper loaded in the tray.
• Print and keep the menu settings page. The original menu settings page will be used to restore the custom settings if necessary.
• Make sure that the Print resolution and Toner darkness on the menu settings page are set to their default values.
• Check the toner cartridge for damage, and replace if necessary.
• Print the advanced print quality samples to see if the problem remains. Use tray 1 to test print quality problems. Look for variations in the print from what is expected.
• Make sure that the correct print driver is used to prevent print problems. If the wrong print driver is installed, incorrect characters could print and the copy may not fit the page correctly.