Oki ML620 User Manual page 83

PROBLEM
Printing slows down
Print direction changes
suddenly to unidirectional.
Print Error warning
The print carriage does not
operate.
Print blurring
The characters are too pale to
display properly on the paper.
A line of print is missing.
The printout differs from the screen display
Printout contains completely
different characters or
symbols.
CAUSE
When the printhead overheats, the printer
automatically starts unidirectional split
printing.
There is contamination on the carriage
shaft.
The Paper Thickness lever position does not
match the paper.
The printer is set to print at high speed.
The ribbon has reached its end-of-life.
The ribbon cartridge is not installed
correctly.
The ribbon has been wound incorrectly.
The ribbon is not transferring properly.
Broken wire pins.
Incorrect print setup for the user's
application.
The application control codes for the
previous print operation are still enabled.
SOLUTION
The printer will return to its original operation
when the printhead temperature drops
sufficiently.
Clean any paper dust and contamination from
the carriage with a dry cloth.
Correct the Paper Thickness lever setting.
Set the speed to normal.
Replace the ribbon with a new one.
Reinstall the ribbon cartridge correctly.
Replace the ribbon cartridge with a new one.
Replace the ribbon cartridge with a new one.
Contact your dealer.
Reselect print setup for the applications
according to priority.
Initialize the printer.
ML620/ML621 User's Guide