Failure Investigation for Electronic Parts Problems with vertical needle movement and reverse stitching
Problems with vertical needle movement
and reverse stitching
Is the connector of the SS-VR PCB
assy. correctly connected to CN1 of
the main PCB assy.?
5 - 12
Are the resistance values for the
Stop/start switch, reverse switch, and
raise needle switch normal?
• Switch resistance values
Switch pressed ...... 1 Ω or less
Switch released ...... ∞
Is the BW switch assy. OFF?
Replace the main PCB assy.
Reconnect it correctly
Replace the SS-VR PCB assy.
Adjust the assembly of the
BW switch assy.