Canon imagePRESS C800 Series Troubleshooting Manual page 45

Chapter 1
Cause
The above symptom occurs when the first side of 2-sided heavy coated paper scrapes against foreign objects including paper dust accumulated on the guide [a] of
the decurler unit.
Service work
1) Open the front cover and remove the supplied cleaning member [a].
2) Open the front left cover [b]. Release the open/close lever [c] of the decurler unit and open the feed guide [d].
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