Failure Analysis - Oki Microline 520 Service Handbook

4.6.03 ALARM/LED Display Troubleshooting Tables
CAUTION:
Always check that all connectors on the printer are making good contact.
Reference Failure Description
Number
1 Space Motor Alarm
2 Printhead Detection Alarm
3 Printhead A/D Alarm
4 Printhead Gap Alarm
5 Printhead Data Transfer Alarm
6 Printhead Type Alarm
7 Printhead Connection Alarm (1)
8 Printhead Connection Alarm (2)
9 Line Feed / Space Motor Driver
Alarm
10 MPU Internal RAM Alarm
11 Program ROM Alarm
12 RAM on Main Control Board
13 CG ROM Alarm

Failure Analysis

Cause
Space motor IPT does not occur
in specified time.
Printhead does not home.
Thermistor is open or +5 vdc
shorted.
Self adjustment was not
successful.
Printhead parity error
was not recovered or print head
was not seated properly.
24 pin printhead is connected in
a 9 pin printer.
Overdrive signal is active but no
current is detected.
Self adjust was not successful.
Head gap is too small or too
narrow.
High driver temperature. The
TSD signal has not changed.
Read/write error
Check sum error
Read/write error
Check sum error
4 - 20 Microline 520/521 Service Handbook
Recommended Action
Refer to RAP 02.
Refer to RAP 03.
Check the printhead connection.
Then, replace the main control
board, the carriage cable, and
the printhead.
Check the printhead connection.
Then, replace the main control
board, the carriage cable, and
the printhead.
Replace the main control board,
the carriage cable, and the
printhead.
Replace the printhead with a 9
pin printhead.
Check the printhead connection.
Then, replace the main control
board, the carriage cable, and
the printhead.
Check the printhead connection.
Then, replace the main control
board, the carriage cable, and
the printhead.
Replace the following: main
control board, line feed motor,
and space motor.
Replace the main control board.
Replace the main control board,
and/or ROM.
Replace the main control board.
Replace the main control board.
P/N 59257803