Kyocera TASKalfa 7002i Service Manual page 1297

C7850: Power source fan motor error
The lock-up is detected for 5s continuously when the power source fan motor drives.
Step Check description
1 Checking the connection
2 Checking the power
source fan motor
3 Replacing the power
source fan motor
4 Firmware upgrade
5 Replacing the engine PWB The engine PWB is faulty.
C7901: Drum unit EEPROM error
The EEPROM in the drum unit cannot be accessed. 1. No response from the device is detected for 5s or more
5 times continuously when reading / writing the data. 2. Data written in 2 points do not match 8 times continu-
ously. 3. Write data and read data does not match 8 times continuously.
Step Check description
1 Resetting the main power
2 Reinstalling the drum unit
3 Checking the connection
Assumed cause
The connector is not prop-
erly connected. Or, the
wire is faulty.
The power source fan
motor does not properly
rotate due to dirt.
The power source fan
motor is faulty.
The firmware is not the lat-
est version.
Assumed cause
The data stored in the
EEPROM in the drum unit
is faulty.
The drum unit is not prop-
erly installed.
The connector is not prop-
erly connected. Or, the
wire is faulty.
7-437
Measures
Clean the terminal of the fol-
lowing wire connectors and
reconnect the connectors. If
there is no continuity, replace
the wire. • Power source fan
motor - Engine PWB
Clean power source fan
motor and check if the fan
can rotate manually. Then,
reattach it.
Execute U037 [Low Volt] and
check the power source fan
motor operation. If the fan
motor does not properly oper-
ate, replace it.
Upgrade the engine firmware
to the latest version
Replace the engine PWB.
Measures
Turn the power switch and
the main power switch off .
After 5s passes, turn the
main power switch and the
power switch on.
Reinstall drum unit BK so that
the connector firmly con-
nects.
Clean the terminal of the fol-
lowing wire connectors and
reconnect the connectors. If
there is no continuity, replace
the wire. • Drum unit - Front
PWB?• Front PWB - Engine
PWB
2WA/2NJ/2RK
Reference
Wiring dia-
gram
Fan
Motors
Attach-
able Direc-
tion
Fan
Motors
Attach-
able Direc-
tion
Firmware
Update
Reference
Detaching
and reat-
taching the
drum unit
Wiring dia-
gram