Fusing Unit Error - Oki B4500 Maintenance Manual

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Fusing unit error (ERROR 170) (ERROR 171) (ERROR 172) (ERROR 173)
• Turn the power off, then back on again.
• Yes Is the thermistor open or shorted? Measure the resistance between thermistor contacts (heater
contacts 120V/2Ω or 240V/7Ω, and thermistor contacts 200KΩ at room temperature) (see
Figure 5-2).
• Yes Replace the fusing unit.
• No Do the thermistor connector is connected to the high voltage/sensor board connector?
• No Connect the thermistor connector property.
• Yes Is the heater of the fusing unit turned on (when the heater is turned on, light is emitted)?
• Yes Check the thermistor connector or replace the main control board or the fusing unit.
• No Is the AC voltage being supplied to the connector for the heater of the power supply board?
(see Figure 5-2)
• No Replace the main control board or the power supply board.
• Yes Check the heater connector cord and the heater connector for poor contact .
43502101TH Rev.1
Heater connector
Figure 5-2
Thermistor connector
Oki Data CONFIDENTIAL
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