Baby Lock BLMY Service Manual page 198

Failure Investigation for Electronic Parts Main motor does not turn
Is the presser foot lifter shaft down?
Is the presser switch resistance
normal?
• Presser switch resistance
Is the NP F2 PCB assy. connector
correctly connected to CN2 on the
main NF3D PCB assy.?
• Replace operation U22 PCB assy.
• Replace main NF3D PCB assy.
• Replace power supply F
From previous page
Y
1 Ω or less
Switch pressed ...
∞
Switch released ...
Y
Y
or
or
N
Lower the presser foot lifter.
N
Replace switch assy.
N
Reconnect it correctly
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