10
Bobbin thread sensor
potentiometer
Needle plate sensor switch
Printed circuit board A relay
(18-pin)
Feed motor
Printed circuit board A relay
(14-pin)
Bobbin thread sensor motor
Drop feed motor
Printed circuit board A relay
carriage
Relay (carriage)
Thread cutter motor
Replacing Electronic Components
Printed circuit board U2
NOTE:
Do not disconnect the connectors by pulling on cord.
To disconnect the connectors, grasp the connector, not the
cord.
To remove:
1. Remove the base plate (see page 3).
2. Remove the setscrew A and cord binder. Disconnect the
connectors.
3. Disconnect the connectors and setscrews B.
Remove the printed circuit board U2.
To attach:
Follow the above procedure in reverse.
Setscrew A
Cord binder
Setscrews B (3 pcs.)
Printed circuit board U2
Board U2 schematic