ELNA Elinita EF72 Service Manual page 46

7. Thread cutter motor
8. Thread tension release motor
9. Driving motor/bobbin winding motor.
Results
* Regarded as good when all the results are correct.
* In case of defect, check again after adjustment or replacement of parts.
Correct condition
Turn the handwheel to move the
needle bar to the zigzag phase (up
position). When pressing the needle
up/down key, the thread cutter motor
is initialized and the buzzer sounds.
Press the start/stop key to proceed
to the next step.
Correct condition
When pressing the needle up/down
key, the thread tension release
motor is initialized and the buzzer
sounds.
Press the start/stop key to proceed
to the next step.
Correct condition
When pressing the needle up/
down key, the motor starts running,
increasing speed evenly. The motor
stops at the needle up position.
The screen shows "OK".
When pressing bobbin winding key
( ), the bobbin winding motor
runs.
8. Turn the power switch off to finish.
44
Faulty condition
The thread cutter motor is not
initialized.
"E4" is indicated.
The caution buzzer sounds when
the thread cutting motor starts
running.
To adjust or replace a part:
Adjust the position of the
sensor.
Replace the thread cutting motor.
Change the printed circuit board A.
Faulty condition
The thread tension release motor is
not initialized.
"E3" is indicated.
The caution buzzer sounds when
the thread tension release motor
starts running.
To adjust or replace a part:
Adjust the position of the
sensor.
Replace the thread tension release
motor.
Change the printed circuit board A.
Faulty condition
The motor does not run.
The screen shows "NG".
The bobbin winder motor does not
run.
The motor does not run smoothly.
To adjust or replace a part:
Replace the driving motor.
Replace the bobbin winder motor
Change the printed circuit board A.