Troubleshooting - Brother BAS-342G Service Manual

10. TROUBLESHOOTING

10. 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.
Turn off the power switch and disconnect the power cord before carrying out troubleshooting.
If the foot switch is depressed by mistake, the sewing machine might start operating and injury could result.
Problem
Work clamp does not
lift.
Work clamp does not
drop.
Work clamp lift amount is
incorrect.
Work clamp does not lift
to the maximum height.
Thread wiper does not
operate correctly.
Lower thread winds to
one side.
Lower thread winding
amount is incorrect.
Thread slips out of the
needle.
139
Cause
Work clamp moves stiffly.
Air tube of presser lifter cylinder is bent
or damaged.
Work clamp lifter lever position is
incorrect.
Cylinder joint position is incorrect.
The thread wiper is obstructing the
needle.
Thread wiper position is incorrect.
Bobbin winder tension
height is incorrect.
Bobbin presser position is incorrect.
Stitches being skipped at the sewing
start.
Upper thread trailing length is uneven.
Position of shuttle race thread guide is
incorrect
CAUTION
Apply a suitable amount of grease to
the sliding parts of the work clamp
slider.
Straighten the bend in the tube or
replace the tube.
Adjust the position of the work clamp
lifter lever.
Adjust the position of the cylinder joint.
Adjust the height of the thread wiper.
Adjust the stroke of the thread wiper.
Adjust the stroke of the thread wiper.
assembly Adjust the height of the bobbin winder
tension assembly.
Adjust the position of the bobbin
presser.
Refer to "Skipped stitches occur".
Adjust the sub-tension.
Adjust the position of the shuttle race
thread guide.
BAS-342G
Remedy Reference
P. 97
P. 94
P. 94
P. 94
Instruction
manual
Instruction
manual
P. 140
Instruction
manual
P. 89