OKIDATA Microline 395 Service Handbook page 120

%RAP 04: Ribbon Homing Error (ALARM 57)
RAP 04: Ribbon Homing Error (ALARM 57)
START
Is the printer the color model?
NO Is shorting plug SP3 of the control board open?
NO Set it open.
YES Go to A.
YES Manually rotate the ribbon shift cam counterclockwise. Does it rotate smoothly?
NO Check the areas listed below.
No paper scrap or foreign matter on the gear
Smooth gear meshing
No friction at each fulcrum of the carriage bracket, roller lever and ribbon shift arm
YES Is cable CN2 on the sensor board connected correctly?
NO Connect it correctly.
YES Is cable CN4 on the control board connected correctly?
NO Connect it correctly.
YES Is there dirt or dust on the ribbon home sensor on the sensor board?
YES Clean the sensor.
NO Go to A.
A
Replace the control board.
Has the problem been resolved?
YES End of procedure.
NO Replace the bail/ribbon motor.
Has the problem been resolved?
YES End of procedure.
NO Replace the sensor board.
ML395 ( 96-02-03 )