If you are comfortable with more advanced diagnostics, you can use the machine's internal Test Mode. To access it, you usually turn the machine on while holding the "Position" (or a similar) key. The exact method varies by model, so refer to your technical manual. Once inside:
Remove the drum that is causing the error.
If the master roll was installed improperly or sustained physical damage, it may tear or crumple abnormally during the disposal phase. riso error a16-525
Ensure the hooks are moving freely and are not damaged. 2. Reset the Machine/Clear Phantom Jams
The most common cause, where the old master simply fails to release from the print cylinder Reddit/r/risograph . If you are comfortable with more advanced diagnostics,
Regularly vacuum or blow out the master making and disposal cavities to keep dust from blinding the optical sensors.
Locate the optical sensors near the master disposal entrance and compression plate. Once inside: Remove the drum that is causing the error
: Inside the disposal unit, a plate compresses the masters to save space. If this plate is stuck or its home-position sensor is dirty, the A16-525 error will trigger.
Check inside the empty compartment for any loose, stray stencils.
If you see a crumpled or partially fed master sheet, gently pull it out in the direction of the normal paper path to avoid tearing.