Locate the rubber disposal rollers and the small glass-faced photo-sensors near the disposal entryway.

The Riso error code indicates the machine is "Waiting for the master to be removed" from the print cylinder (drum). This error typically occurs when the printer's sensor fails to detect that a master has been successfully ejected into the disposal box. Common Causes

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- If the sensor is clean and the drum is clear, the issue might be mechanical. On some forums, users have reported success by manually rotating the drum's internal gear. - Action: With the machine off and drum removed, check the small black strip on the drum's surface. Is it torn or peeling? If so, it needs to be replaced. If it's intact, an advanced trick is to manually rotate the drum's drive gear from inside the machine's back panel to force it through its cycle and reset the sensor position. This is a more advanced step and may be best left to a service technician if you are not confident .

Darken the light absorber strip with a black marker or replace it How to Prevent Future A16-525 Errors

: Manually pull out the print cylinder. If a master sheet is present, open the clamp manually and slide the master off into the trash.