Troubleshooting; Sewing - Brother Z-8550A Instruction Manual

15. TROUBLESHOOTING

• 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
purchase.
Wait at least 5 minutes after turning off the power switch and disconnecting the power cord from the wall outlet
before opening the face plate of the control box. Touching areas where high voltages are present can result in
severe injury.
Turn off the power switch and disconnect the power cord before carrying out troubleshooting.
The machine may operate if the treadle is depressed by mistake, which could result in injury.

15-1. Sewing

Items with a "*" in the "Page" column should only be checked by a qualified technician.
Problem
1 Upper thread is not tight.
2 Lower thread is not tight
• Is the upper thread tension too weak, or is the lower thread tension
too strong?
Adjust the upper thread tension or lower thread tension.
• Was the thread threaded through the thread guide of the bobbin
case in accordance with the type and thickness of the sewing
article's material.
Use thread guide A or B in
accordance with the material being
sewn.
0573M
• Is the lower thread tension too weak, or is the upper thread tension
too strong?
Adjust the lower thread tension or upper thread tension.
• Was the thread threaded through the thread guide of the bobbin
case in accordance with the type and thickness of the sewing
article's material.
Use thread guide A or B in
accordance with the material being
sewn.
0574M
DANGER
CAUTION
Possible cause
Z-8550A, 8560A
15. TROUBLESHOOTING
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3556M
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