Check the display for error messages, The toner may be low, The scanner glass may be dirty – Lexmark 436 User Manual
Page 191: The copy is too light or too dark, Check the quality of the original document, Check the document placement, Unwanted toner is in the background, Patterns (moiré) appear in the output
Check the display for error messages, The toner may be low, The scanner glass may be dirty | The copy is too light or too dark, Check the quality of the original document, Check the document placement, Unwanted toner is in the background, Patterns (moiré) appear in the output | Lexmark 436 User Manual | Page 191 / 235