Ricoh Aficio 270 - SC546: Unstable Fusing Temperature

Trouble-
shooting
SERVICE CALL CONDITIONS
SM 7-9 A265/A267
SC543: Fusing overheat error
-Definition- [A]
A fusing temperature of over 231
°
C is detected for 1 second by the fusing
thermistor.
- Possible causes -
•
Fusing thermistor defective
•
Power supply board defective
SC544: Fusing low temperature error
-Definition- [A]
A fusing temperature of lower than 100
°
C is detected for 1 second by the fusing
thermistor.
- Possible causes -
•
Fusing thermistor defective
•
Power supply board defective
•
Poor connection of the fusing unit
SC546: Unstable fusing temperature
Definition: [A]
Fusing temperature more than 60
°
C: The fusing temperature does not rise 2
°
C
or more within 6 seconds after the fusing lamp has been on.
Fusing temperature 60
°
C or less: The fusing temperature does not rise 2
°
C or
more during a 6 second interval (the 6 s timer starts 14 s after the fusing lamp
turned on).
Possible Causes:
•
Thermistor defective
•
Poor connection of the fusing unit
•
Power supply unit defective
SC547: Zero cross signal malfunction
-Definition- [A]
Zero cross signals are not detected within a certain period.
- Possible causes -
•
Power supply board defective
•
IOB defective
•
BICU defective