Oki ML520 - Manual (Page 187)

Page: 129
Service Guide ML520/521
Chapter 4 Failure & Repair Analysis
4.6.03 ALARM/LED Display Troubleshooting Tables
CAUTION:
Always check that all connectors on the printer are making good contact.
Reference
Number Failure Description Cause Recommended Action
1 Space Motor Alarm Space motor IPT does
not occur in specified
time. Refer to RAP 02.
2 Printhead Detection
Alarm Printhead does not
home. Refer to RAP 03.
3 Printhead A/D Alarm Thermistor is open or +5
vdc shorted. Check the printhead
connection. Then
replace the main control
board the carriage cable
and the printhead.
4 Printhead Gap Alarm Self adjustment was not
successful. Check the printhead
connection. Then
replace the main control
board the carriage cable
and the printhead.
5 Printhead Data
Transfer Alarm Printhead parity
error<R>was not
recovered or print head
was not seated properly. Replace the main control
board the carriage cable
and the printhead.
6 Printhead Type
Alarm 24 pin printhead is
connected in a 9 pin
printer. Replace the printhead
with a 9 pin printhead.
7 Printhead
Connection Alarm
(1) Overdrive signal is
active but no current is
detected. Check the printhead
connection. Then
replace the main control
board the carriage cable
and the printhead.