Pfaff Espression line Owner's Manual page 46

Is a correct spool cap used?
Is the best spool pin position used?
Is the stitch plate hole damaged?
Bobbin thread breaks
Is the stitch plate hole damaged?
Is the bobbin area clean?
Is the bobbin wound correctly?
The seam has uneven stitches
Is the thread tension correct?
Is a correct needle used?
The machine does not feed or feeds irregularly
Has sewing lint collected between the feed
dogs?
Have your sewing machine serviced regularly by your local authorized PFAFF® dealer!
than words.
Non-original parts and accessories
5:4
thread spool.
Change the stitch plate.
Check the bobbin thread.
Change the stitch plate.
Clean lint from bobbin area and use only the original
Wind a new bobbin.
Check needle thread tension and the threading.
Change the thread.
Check bobbin winding.
Insert a proper needle correctly as described in
chapter 2.
Check how the machine is threaded.
brush.