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4 Fusing unit error (ERROR 71) (ERROR 72) (ERROR 73)
• Turn the power off, then back on.
• Does the fusing unit error occur immediately?
• Yes Is the thermistor open or shorted?
Measure the resistance between
thermistor contacts (about 220kΩ at
room temperature) (see Fig. 6-2 or
see 7.3).
• Yes Replace the fusing unit.
▼
• No Do the thermistor contacts touch the contact assembly properly when the
fusing unit is mounted in the printer (see Fig. 6-4 contact
F
)?
• No Adjust the contact.
▼
• Yes Replace the Main Control PCB or power supply board.
▼
• No Does the fusing unit error occur about 60 seconds after the power is turned on?
• No Check the thermistor for poor contact or replace the Main Control PCB.
▼
• Yes Turn the power off, then back on.
• Is the heater of the fusing unit turned on (when the heater is turned on, light is emitted)?
• Yes Check thermistor contacts or replace the Main Control PCB or the fuser unit.
▼
• No Is the heater or the thermostat open?
Measure the resistance between the heater contacts (normal resistance: about 0Ω)
(see Fig. 6-2 or see 7.3).
• Yes Replace the fusing unit.
▼
• No Is the AC voltage being supplied to the contacts for the heater of the contact assembly?
(Refer Fig. 6-2)
• No Replace the Main Control PCB or the power supply board.
▼
• Yes Check the heat contact of the fusing unit and the contact assembly for poor contact
(see Fig. 6-4 contact
G
).
Themistor contacts
Heater contacts
Figure 6-2
