Four-Digit Alphanumeric Characters Appear On Lcd - Canon PIXMA GM4040 Online Manual

Four-Digit Alphanumeric Characters Appear on LCD

A message appears on the printer's LCD or your computer screen.
Some errors may display four-digit alphanumeric characters along with the error message. The characters
represent a "support code" (error number).
For details on each support code, see List of Support Code for Error.
405