Ricoh FT 4015 Service Manual page 218

SERVICE CALL CONDITIONS
CODE #55 — FUSING ERROR 4
- Definition -
•
The temperature value output by the thermistor has not changed at all
16 (NA) or 20 (EU) seconds after the main switch is turned on.
•
The temperature change detected by the thermistor is more than 20°C
within any one second after the 16 (NA) or 20 (EU) seconds warm up
time after the main switch is turned on.
To clear this error, refer to note 3 at the beginning of this chapter.
- Possible Causes -
•
Thermistor open
•
Defective main control board
•
Defective ac drive/dc power supply board
•
Fusing lamp open
•
Poor thermistor connection
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20 December 1996