2PR
1-4-24
7404 Developing unit Y non-installing error
The EEPROM of the developing PWB Y
does not communicate normally.
Incompatible developing unit Y is
installed.
Faulty connection
of the connector
between the devel-
oping PWB Y and
drum relay PWB.
Check the installation of the developing unit
Y and drum relay PWB and reinstall them if
necessary (See page 1-5-12).
Defective harness
between drum
relay PWB (YC2)
and engine PWB
(YC619), or
improper connec-
tor insertion.
Reinsert the connector. Also check for conti-
nuity within the connector harness. If none,
remedy or replace the harness.
Installation of
incompatible
developing unit Y.
Install developing unit Y compatible with the
specifications to the printer.
Defective toner
sensor Y.
Replace the developing unit Y (See page 1-
5-12).
Defective engine
PWB.
Replace the engine PWB (See page 1-5-
28).
7411 Drum unit K non-installing error
The EEPROM of drum PWB K does not
communicate normally.
Incompatible drum unit K is installed.
Faulty connection
of the connector
between the drum
PWB K and drum
relay PWB.
Check the installation of the developing unit
K and drum relay PWB and reinstall them if
necessary (See page 1-5-12).
Defective harness
between drum
relay PWB (YC1)
and engine PWB
(YC34), or
improper connec-
tor insertion.
Reinsert the connector. Also check for conti-
nuity within the connector harness. If none,
remedy or replace the harness.
Installation of
incompatible drum
unit K.
Install drum unit K compatible with the spec-
ifications to the printer.
Defective drum
PWB K.
Replace the drum unit Y (See page 1-5-14).
Defective engine
PWB.
Replace the engine PWB (See page 1-5-
28).
Code Contents
Remarks
Causes Check procedures/corrective measures