2GZ/2G1-2
1-4-24
6410 Fuser unit connector insertion prob-
lem
Absence of the fuser unit is detected.
Fuser unit connec-
tor inserted incor-
rectly.
Reinsert the fuser unit connector if neces-
sary.
Defective fuser unit
connector.
Replace the fuser unit.
6420 Fuser unit fuse cut problem
The fuse cannot be cut, When replacing
the fuser unit, the fuse cannot be cut in
3 s after the fuse cut signal is turned on.
Poor contact in the
connector termi-
nals.
Check the connection of connector YC10 on
the engine PWB and the continuity across
the connector terminals. Repair or replace if
necessary.
Fuser unit connec-
tor inserted incor-
rectly.
Reinsert the fuser unit connector if neces-
sary.
7400 Developing unit connector insertion
problem
Absence of the developing unit is
detected.
Developing unit
connector inserted
incorrectly.
Reinsert the developing unit connector if
necessary.
Defective develop-
ing unit connector.
Replace the developing unit.
7410 Drum unit connector insertion prob-
lem
Absence of the drum unit is detected.
Drum unit connec-
tor inserted incor-
rectly.
Reinsert the drum unit connector if neces-
sary.
Defective drum unit
connector.
Replace the drum unit.
7800 Broken external thermistor wire
The thermistor output value is 4.5 V or
more.
Poor contact in the
connector termi-
nals.
Check the connection of connector YC14 on
the engine PWB and the continuity across
the connector terminals. Repair or replace if
necessary.
Defective humidity
sensor.
Replace the humidity sensor.
7810 Short-circuited external thermistor
The thermistor input value is 0.5 V or
less.
Poor contact in the
connector termi-
nals.
Check the connection of connector YC14 on
the engine PWB and the continuity across
the connector terminals. Repair or replace if
necessary.
Defective humidity
sensor.
Replace the humidity sensor.
7900 Drum EEPROM error
Reading from or writing to EEPROM
cannot be performed.
Poor contact in the
connector termi-
nals.
Check the connection of connector on the
engine PWB and the continuity across the
connector terminals. Repair or replace if
necessary.
Defective drum
unit.
Replace the drum unit.
7910 Developing unit EEPROM error
Reading from or writing to EEPROM
cannot be performed.
Poor contact in the
connector termi-
nals.
Check the connection of connector on the
engine PWB and the continuity across the
connector terminals. Repair or replace if
necessary.
Defective develop-
ing unit.
Replace the developing unit.
Code Contents
Remarks
Causes Check procedures/corrective measures