Failure Investigation for Electronic Parts Bobbin winding cannot be done
5 - 14
Bobbin winding cannot be
Is the bobbin winder mechanism
assembled and attached correctly?
Is the resistance between the bobbin
winder assy. connector pins 1 & 2
• Bobbin winder shaft in bobbin wind
position .......... 1 Ω or less
• Bobbin winder shaft not in bobbin
wind position ... ∞
Is the FFC connected correctly
between the main PCB (CN5) and the
motor PCB (CN1)? Are both connector
locks applied correctly? Is the FFC
free breakage or short circuit?
Replace the main PCB assy.,
Replace the motor PCB assy.
Reassemble the bobbin
Replace the BW switch assy.
Connect the FFC or replace it.