Datamax Prodigy Plus Operator's Manual page 147

3) The media slips or does not properly advance:
Possible cause and solution:
The Head Level Adjustment Knob setting is adjusted too high,
re-adjust the Head Level Adjustment Knob, (see Section 5.3.1).
The Platen Roller is dirty, clean the Platen Roller.
4) Uneven printing or print too light:
Possible cause and solution:
The Hinge Plate is open or unlatched, re-latch the hinge plate,
(see Section 5.1, steps 6, 7, and 8).
The Head Level Adjustment Knob setting is adjusted too high,
re-adjust the head level adjustment knob, (see Section 5.3.1).
The darkness is adjusted too low, readjust.
5) Poor print quality:
Possible cause and solution:
The Printhead is dirty, clean the printhead, (see Section 5.1).
The wrong ribbon/paper combination is being used, use a
different type of ribbon and/or paper.
The Printhead temperature is too high or too low. Use software
control to adjust the heat settings or darkness via the optional
LCD/Keypad Front Panel.
The Printhead is bad, ( see Section 5.3.3).
6) No display
Possible cause and solution:
Display contrast set too low, turn the contrast adjustment
clockwise until the display appears.
The LCD display is defective, return the Printer for service.
Prodigy Max Operator's Manual
power light is on (LCD/Keypad front panel):
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