Canon LASER CLASS 730i Service Manual page 59

LASER CLASS 730i/720i/710 Chapter 2: Technical Reference
10. Abnormally high-temperature sub thermistor error detection
The CPU stores the temperature of the sub thermistor at the timing the leading edge of print
paper reaches the fixing heater, and monitors the temperature rise of the thermistor during
270 mm of the print paper.
If the CPU detects that the sub thermistor rises to 80°C or more, it determines an
abnormally high-temperature sub thermistor error and notifies it to the SCNT board.
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