12) Print Speed Is Slow. (Performance Is Low.); Print Speed Is Slow. (Performance Is Low.); 13) Option Unit Cannot Be Recognized; Option Unit Cannot Be Recognized - Oki B721 Maintenance Manual

Oki Data CONFIDENTIAL
(11-3)

All fans of the printer do not rotate.

Check item
(11-3-1) 24V power supply
PU/CU board fuses Check if the fuses F1 is not open-circuit or
F1, F503 not.
24V power that is Check the power supply voltages at the
supplied to the PU/ POWER connector
CU board. The follow voltage must appear respectively.
Pins-17, -18, -19, -20, -21: 0VP
Pins-11, -13, -14, -15, -16: 24V

6.5.2.(12) Print speed is slow. (Performance is low.)

(12-1)

Print speed decreases.

Check item
(12-1-2) Media Weight setting
Media Weight that Check if the wrong Media Weight has been
is specified for the specified or not.
print
45487001TH Rev.1
Actions to be taken
Check work
at NG
Replace the
PU/CU board.
Replace the low
of the PU/CU board. voltage power
supply.
Actions to be taken
Check work
at NG
Correct the
Media Weight.

6.5.2.(13) Option Unit cannot be recognized.

(13-1)

Option try unit cannot be recognized.

Check item
(13-2-1) Option try board
Option try unit Check if the option try unit specification is
being used or not.
(13-1-2) Check the system connection
Check the system Check that the cable between the PU/CU
connection from the board option connector
PU/CU board to the board is normally connected.
option tray board
(GOH-12 PCB).
Square connector Check if any foreign material exists in the
connecting the connecting portion of the square connector.
option tray unit to
the printer.
Square connector Is the terminals of the square connector
connecting the damaged?
option tray unit to
the printer.
(13-2-3) Check the control signals.
Check the control Check the control signal that is output from
signal that is output the PU board option connector
from the PU/CU Pin-8: OPTCNT2 (PU
board to the option Pin-9: TXD (PU
tray board (GOH-12 Pin-10: RXD (2nd
PCB).
6. Troubleshooting procedure
Actions to be taken
Check work
at NG
Replace the
option tray unit.
Correct the
to the option tray connections.
Remove
the foreign
material.
Replace the
connector.
Pin-9: Replace
. the PU/CU
2nd) board.
2nd) Pin-10: Replace
PU) the option tray
board.
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