Instructions for Resetting the Drum on the OKI B433dn Series

Background

The OKI B433dn series printers may display the message [Please replace the drum.] and stop printing after a certain number of pages have been printed. In such cases, drum replacement can be avoided by performing a proper reset, allowing the component to remain in service.

The drum for this model cannot be reset through software or printer buttons, as it does not use a physical drum chip.

This article details a hardware-based method for resetting the drum, enabling engineers and technicians to resolve this issue efficiently.

Figure 1: Prompt

Solution

Step 1: Preparation

Prepare two insulated thin wires and a 1/16A fuse. Turn off the printer and ensure it is fully powered down. Open the front cover and remove the drum.

Figure 2: Tool Preparation

Step 2: Contact Connection

Locate the two contacts on the printer and connect them using the two insulated wires (as shown in figure 3).

Safety Warning: Ensure the exposed wire ends do not contact the printer's metal casing to prevent a short circuit.

Figure 3: Contacts

Step 3: Fuse Installation

Connect the free ends of the two wires to each end of the 1/16A fuse (as shown in Figure 4). Ensure the connections are secure and there are no loose or improper contact.

Figure 4: Fuse Connection

Step 4: Reset Standby

Reinstall the drum and close the cover. Turn on the printer. The fuse will automatically blow, preparing the drum unit for reset.

Step 5: Reset Procedure

Once the printer has started up and displays a ready status, power it off and remove the drum unit again. Remove the insulated wires and fuse tube connected to the printer contacts, then reinstall the drum into the device. The reset process is now complete.

Figure 5: Ready Status

Troubleshooting Common Issues

If the printer does not function properly after the reset, consider the following possible causes:

1. Short Circuit

An exposed wire may have contacted the printer’s metal casing causing a short circuit. Reinsulate the wire and repeat the procedure.

2. Fuse Issue

An incorrect fuse rating (non 1/16A) or a defective fuse may prevent it from blowing as intended. Replace it with a compliant 1/16A fuse and repeat the reset.

3. Poor Contact

A loose connection between the insulated wire and the printer's contacts may result in an open circuit. Recheck and secure the connection to ensure proper contact.

Conclusion

For printers like the OKI B433dn that do not use a drum chip, the message [Replace the Drum] may appear and the printer ceases printing. The drum can be reset through professional reset operations, restoring normal printing functionality and effectively reducing consumable costs.