• In 100 V models, only one of the AC lines for the fusing unit is shut off when you turn off the main power; the other line carries current even when you turn off the main power switch. Because of this, turn off the main power switch, and also always pull out the AC power cord from the wall socket before doing replacement.
  • Because there is a danger of burns on contact with hot parts of the fusing unit, start work when the temperature drops to a low enough temperature.
  • To clear SC544-02 or SC554-02, replace the fusing unit or install a fuse (provided in the heating sleeve belt unit) in the fusing unit. If you will install a new fusing unit, follow the procedure below to clear SC544-02 or SC554-02.
    1. Install a new fusing unit.
    2. Clear SC544-02 or SC554-02 with SP5-810-002
    3. Turn the machine off and on.

  • MP 2555 SP/3055 SP/3555 SP
    When the fusing unit is used past its PM cycle, the fusing unit may break, causing a service call. Therefore, the machine displays a warning on the operation panel at 240K pages and stops at 260K pages.
  • MP 4055 SP/5055 SP/6055 SP
    When the fusing unit is used past its PM cycle, the fusing unit may break, causing a service call. Therefore, the machine displays a warning on the operation panel at 320K pages and stops at 350K pages.

  • If you replace a whole fusing unit, you do not need to perform SP3-701. This is because the machine detects a new unit automatically. If you replace only a part of the fusing unit, however, such as the pressure roller, you must set SP3-701 for that part.

  1. Open the right cover.
  2. Remove the screws on the fusing unit [A] and disconnect the connectors (x2, x2).
    • Do not pull out the fusing unit now. The fusing unit is still connected to the machine.

    • When disconnecting the harness, hold the connector as shown below in order to avoid breaking the connector pins.

  3. Remove the fusing unit connector cover [A].

    • Attach the fusing unit connector cover by fitting the space on the connector cover [A] (surrounded by red dashes in the diagram) and the frame of the fusing unit [B] together when installing.
    • The connector cover must be attached before screwing in the fusing unit.

  4. Remove the connector [A]. (x1)

  5. Pull out the fusing unit [A].

    • When installing the fusing unit, attach the rear screw first, then attach the front screw.