• Please check the following points before calling for repairs or service.
• If the following remedies do not fix the problem, turn off the power switch and consult a qualified technician or the place of
Wait at least 5 minutes after turning off the power switch and disconnecting the power cord from the wall outlet before
opening the the control box cover. Touching areas where high voltages are present will result in serious injury from
Turn off the power switch and disconnect the power cord before carrying out troubleshooting, otherwise the machine
may operate if the foot switch is depressed by mistake, which may result in injury.
. Upper thread breakage / lower thread breakage
Items with a "*" in the "Page" column should only be handled by a qualified technician.
Upper thread amount
Upper thread threading
Lower thread threading
Flaw or abrasion on the
Arm thread guide C position
Upper thread tension
Thread take-up spring
tension and height
Needle installation height
Blunt needle tip or burr
Needle and thread
Thread the upper thread correctly.
Thread the lower thread correctly.
Polish with buff or replace the part.
Especially, pay attention to finishing around needle
Adjust the arm thread guide C position.
Adjust the upper thread tension appropriately.
Loosen the thread take-up spring tension or lower the
height to such a degree that does not cause double
Attach the needle so that the long groove on the
needle is at the front.
Insert the end of the needle shank so that it touches
the top edge of the needle hole of the needle bar.
Replace needle that fits the thread.
(Continued on next page)