Go to the Previous PageGo to the Main ViewGo to the Next PageGo to a printer friendly version of this document
Chapter 6 Problem Solving & Maintenance
(User's Guide ML590/ML591)
Problem Solving
Problem: Nothing happens when I turn on the printer.
Solution: The printer may not be plugged in. Check the power cord connection to the outlet and to your printer. If you're using a power strip, make sure it's turned on. Check to be sure that the circuit breaker hasn't tripped.

Problem: The printer doesn't print when the computer sends data.
Solutions: (1) The printer may be deselected. If the SEL light is out, press the SEL button to select the printer. (2) The printer cable may be loose: check to be sure that it is securely connected to both the printer and your PC.

Problem: I've installed a brand new ribbon and the printing is smeared and streaked.
Solution: The shield on the ribbon may be either loose or missing. Move the printhead to the center of the platen (CAREFUL! the printhead may be HOT!) and lift off the ribbon cartridge. If the ribbon shield is loose, secure it in place properly. If it's missing, locate it and reinstall it.

Problem: The printing is too light or too dark.
Solution: The head gap setting needs adjustment. Enter the Menu Mode and change the setting for Printhead Gap Adjust under the Group Setup. The default setting is 0. If the printing is lighter, change the setting to-1; if it's darker, change it to +1.

Problem: The ALARM light is on and the Character Pitch 15 light is flashing.
Solution: This indicates a paper loading error. Press the SHIFT and RESET buttons simultaneously. Before trying to load paper again, check to be sure that you have the paper lever in the correct position for the paper path you're using. If the paper lever is in the correct position and you're using continuous-form paper, check to see if the paper is properly on the tractors and has not jammed up.

Problem: The first line is printing too far down on the page and I can't get it any higher using the SHIFT-LF/ Micro Feed Down keys.
Solution: The setting for the Top of Form will be restricted if you have the Form Tear-Off feature engaged when you set the Top of Form. To correct for this, enter the Menu Mode and change the setting for Form Tear-Off in the Rear-Feed group ( or in the Bottom Feed group if you have the optional bottom-feed tractor installed) to Off. Then exit the Menu and set the Top of Form. When the Top of Form is set, enter the Menu Mode again and change the Form Tear-Off setting back to your original setting. (See Chapter 5 for information on the Menu Mode.)

Problem: I need to load paper, but the Alarm light is not on.
Solution: Press and release the SEL button, then hold the SHIFT button and press the RESET (Character Pitch) button. The ALARM light will come on and you will be able to load the paper.

Problem: My word processor files don't print the way I have the menu and front panel set.
Solutions: Before sending a file to the printer, many word processors send either an initialization string or an I-Prime signal to the printer. The initialization string contains commands that change the printer to a default set of features. These commands override front panel or Menu settings. To set your printer to ignore the reset command, enter the printer Menu and change the Reset Inhibit item in the Set-Up group to Yes. Please note that while this stops the reset command from resetting your printer, other commands in the initialization string may still override the printer Menu and/or front panel settings. The I-Prime signal is sent over the parallel interface (pin 31) and automatically overrides any settings you have made using the front panel. To eliminate this problem, enter the printer Menu and change the I-Prime item in the Parallel I/F group to Invalid.

Problem: The Print Quality and Character Pitch buttons on the front panel won't work.
Solution: The Operator Panel Function item on the printer menu can be used to disable these buttons. If the printer is a part of a customized system or if it is used by a number of people, the system manager may have used this option to make sure the printer is always set properly.

Problem: Static electricity causes my continuous-form paper to stick.
Solution: Sometimes static charges can build up on continuous-form paper, making it cling to the paper separator. If you have this problem during high-volume printing jobs, try moving the paper guides together so that the paper rests on the guides rather than on the separator itself.
Oki Data has taken care to insure that the information is complete, accurate and up-to-date. However, Oki Data assumes no responsibility for errors or omissions which may occur. All the information provided is subject to change from time to time at the sole discretion of Oki Data.
Copyright 2018, Oki Data, Americas, Inc.