Toshiba e-studio 2555c, Service Manual

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© 2012-2013 TOSHIBA TEC CORPORATION All rights reserved e-STUDIO2555C/3055C/3555C/4555C/5055C
OUTLINE OF THE MACHINE
3 - 81
[ 1-2 ] Temperature detection section
Fuser unit error status counter control
•
To enhance the safety of the fuser unit section, the following protection is provided: When a third
[C445] error has occurred after two consecutive [C445] errors, the IH coils are not turned ON and an
error code [C446] is displayed immediately even if the operator turns the power OFF and then back
ON. However, if the equipment goes into the ready state normally with the fuser unit error status
counter value “5”, the counter is cleared to “0”.
• If any of the error codes [C445] to [C449] is displayed but the error is still not cleared and the heater
lamp is not turned ON even after the thermistor, thermostat or heater lamps were repaired, check
the fuser unit error status counter value in the Setting Mode (08-2002) to clear the value to “0”.
Remarks:
The fuser unit error status counter never has any values other than 0 to 66. If the counter value is
”62” or over, data in EPROM or EEPROM may possibly have been ruined due to causes such as
leakage from the chargers. In this case, check the bias, high-voltage transformers and needle
electrodes to see if any of them is defective, and also recheck all the data in the EEPROM.
• When the thermistors detect overheating, the engine CPU determines an error code and the fuser
unit error status counter value. After turning OFF each output (from the heater lamp, exposure lamp,
control panel, motors and so on) to protect the fuser unit, the engine CPU shuts OFF power supply
to the main power switch.
Error code: C449
Counter value of the fuser unit error status: 9, 22, 23, 25, 27, 29 (08-2002)
The thermistors continue detecting abnormal temperatures even after an error code and a counter
value are determined. Even if the main power switch is turned ON immediately, the switch is
automatically turned OFF unless otherwise the surface temperature of the fuser belt goes lower
than the abnormal temperature detected. In this case, therefore, wait unit the surface temperature of
the fuser belt becomes lower than the abnormal temperature detected, and then turn ON the main
power switch. Then check the counter value while you are waiting for the main power switch to be
automatically turned OFF. After confirming that it is a fuser unit abnormality, correct the subject part
in the unit and clear the counter value to "0" so that the equipment can be started up normally.