C0500: Fuser Warm Up Error - NEC NEFAX 671 Service Manual

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C0500: Fuser warm up error

<Detection Timing>
• The voltage of the Thermistor remains low for a predetermined period of time when a
warm-up cycle is started.
• The temperature detected by the Thermistor remains lower than a reference value for a
predetermined period of time for the period of time that begins 5 sec. after, and ends 9
sec. after, the start of the warm-up cycle (where the temperature detected by the Ther-
mistor is 80 °C or less).
• The temperature detected by the Thermistor does not increase for a 3-sec. period or
more for the period of time that begins after the lapse of a predetermined period of time
after the Fusing Roller Heater Lamp has been turned ON and ends when the lamp is
turned OFF.
• The Fusing Roller Heater Lamp remains ON for a 30-sec. period or more (except during
the period through which the Main Motor remains energized).
<Troubleshooting Procedures>
Fusing Unit
Thermistor (TH1)
Fusing Roller Heater Lamp (H1)
Step Action
1 Replace Thermistor (TH1).
2 Replace Fusing Unit.
3 Replace Controller/Mechanical
Control Board (PWB-P).
4 Replace Power Unit (PU1).
Description
Relevant Electric Parts
Controller/Mechanical Control Board (PWB-P)
Thermostat (TS1)
Power Unit (PU1)
Ref. Page
Control Signal
☞ D-28
☞ E-7
☞ D-12
☞ D-15
T-18
WIRING DIAGRAM
Location
(Electric Parts)
– –
– –
– –
– –