Lexmark 2480 - Forms Printer B/W Dot-matrix, Service Manual

Page: 37 / 170

Diagnostic Information
2-19
24xx
2 Printer power
sometimes turns
off. The cause of this problem may be that the
power circuit is failing, or the wiring is
intermittently open. Check the following in
sequence:
1. Check the user’s outlet voltage and be
sure it is within tolerance.
2. Check the continuity of the power cord.
3. Disconnect the power supply cable from
connector CN12 on the logic board. Turn the
printer power on and check all dc output
voltages at CN12-1, CN12-2 and CN12-6.
Verify the following output voltages:
CN12 - 1 (+40 V dc ±10%)
CN12 - 2 (+40 V dc ±10%)
CN12 - 3 (GND)
CN12 - 4 (GND)
CN12 - 5 (Signal GND)
CN12 - 6 (+5 V dc ±5%)
• If one of the voltages is 0, go to “Power
Service Check” on page 2-27 .
• If the voltages are not 0 but are incorrect,
replace the power supply unit.
3 Intermittently poor
print quality. • Remove paper jams from the paper path.
• Clean all feed roller surfaces.
• Clean the ribbon shield and printhead.
• Clean the platen surface.
• Install the ribbon cartridge correctly. If the
ribbon has reached end of life, have the user
replace the ribbon cartridge.
FRU/Symptom Action