4.4.6. Fuser Temperature Control Circuit

The fuser temperature is controlled by IC004 ( Engine CPU ). IC004 has an analog to digital ( A/D ) converter ( AN0-AN7 ).
Thermistor TH is connected to IC004 ( AN0 ). When IC004 ( Pin31 ) is low, Q010 is turned off. And Q4 is turned on.Then Heat lamp
inside fuser unit is turned on.
Abnormal temperature detection circuit consists of the following 2 sub-sections.
1. Abnormally Low Temperature Detection
Abnormally low temperature is detected by IC004 ( Engine CPU ) programming.
2. Abnormally High Temperature Detection
Abnormally high temperature is detected by IC004 ( Engine CPU ) programming. When front door is opened, the fuser lamp is
shut off.
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KX-P7105 / KX-P7110