Canon MultiPASS C50 Service Manual page 174

Part 1: Facsimile
6.2.5 PRINT test
Pressing the 3 button from the test mode menu selects the print test. This test prints various patterns. For
servicing, use the 3-7: CHECKERS pattern (press the 7 button from the print test menu). The other
patterns are not to be used since they are for development and factory personnel. End this test by pressing
the STOP button.
Check the pattern for the following:
NOTE
Figure 3-29 Print Test Pattern Check
If the print test is normal, make a copy of a document. If the copy is faulty, the reading
section is faulty.
Check for any vertical or horizontal white
stripes on the black squares.
Also, check that all the squares have
straight edges on all four sides.
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