5 - 10
Failure Investigation for Electronic Parts Cannot sew button holes well
Cannot sew button holes well
With the BH lever down, are the
resistance values between BH switch
connector pins 1 & 2 and pins 2 & 3
normal?
• BH lever pulled forward
Pins 1 - 2…1
Ω
or less, pins 2 - 3…
∞
• BH lever pushed back
Pins 1 - 2…
∞
, pins 2 - 3…1
Ω
or less
Is the resistance between BH lever
switch connector pins 4 & 5 normal?
• BH lever down …… 1
Ω
or less
• BH lever up ……….
∞
Change to correct presser
N
Replace main NF3D PCB assy.
Y
Y
Is the correct presser being used?
N
N
Y
• Adjust BH lever
or
• Replace BH switch assy.
• Adjust BH lever
or
• Replace BH switch assy.
Summary of Contents for BLMY
Page 1: ......
Page 2: ......
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Page 19: ...1 8 ...
Page 21: ...2 2 Main parts location diagram Main unit ...
Page 30: ...2 11 Disassembly Electrical parts and motors location diagram Main unit ...
Page 37: ...2 18 Thread tension mechanism location diagram Main unit ...
Page 43: ...2 24 Bobbin winder mechanism location diagram Main unit ...
Page 49: ...2 30 Needle bar presser mechanism Upper shaft mechanism location diagram Main unit ...
Page 53: ...2 34 Needle presser module breakout diagram 78 Modules ...
Page 66: ...2 47 Disassembly Feed and bobbin module breakout diagram Modules ...
Page 75: ...2 56 Thread cutter module breakout diagram Modules ...
Page 79: ...2 60 ...
Page 81: ...3 2 Needle bar presser mechanism upper shaft mechanism location diagram Main unit ...
Page 90: ...3 11 Assembly Bobbin winder mechanism location diagram Main unit ...
Page 94: ...3 15 Assembly Thread tension mechanism location diagram Main unit ...
Page 102: ...3 23 Assembly Electrical parts and motors location diagram Main unit ...
Page 109: ...3 30 Main parts location diagram Main unit ...
Page 120: ...3 41 Assembly Needle presser module breakout diagram 78 Modules ...
Page 139: ...3 60 Feed module breakout diagram Modules ...
Page 155: ...3 76 Thread cutter module breakout diagram Modules ...
Page 161: ...3 82 ...
Page 191: ...4 30 ...
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