Power off the printer and open Door B.
Remove the waste toner bottle (WTB).
Remove the imaging kit.
Open the front door and remove the Transfer Module. To do so, proceed to Lexmark MobileTech, enter the printer model, select Parts removal > Front removals > Transfer module removal.
Check the three High Voltage Power Supply (HVPS) contacts to make sure they are visibly protruding through the frame openings (B). Also ensure they are free to move (spring-load up and down without binding) and not stuck (A).
Reseat the HVPS and make sure that the contacts freely move. Refer to Lexmark MobileTech using the same printer model chosen earlier and select Parts removal > Front removals > HVPS removal.
If the issue persists, continue with the succeeding troubleshooting steps.
Using a lint-free cloth, wipe the printhead lenses (A) making sure to check for any toner debris.
Check that the HVPS cable is properly connected on both the power supply and controller board ends.
If the issue still occurs after going through the preceding steps, replace the Transfer module.
Should the issue persist after replacing the Transfer module, replace the HVPS.