-73-
PROBLEM
CAUSE
CORRECTION
8. During thread
winding, the
motor starts,
but stops
immediately.
1. When the motor stops about one second after
starting during thread winding
Is the bobbin winder switch normal?
Is the resistance between 1-2 on connector CN3
(red) normal?
On.......... 1
Ω
max.
Off.......... Infinite
2. Others
1. Replace the bobbin winder
switch assembly.
2. Replace the main PC board
assembly.
9. Sewing
machine does
not operate
normally when
foot controller
pressed.
1. Is the foot controller normal? Does the resistance
across the controller plug vary between 0 and 10 k
Ω
?
2. Is the resistance normal between 2-3 of CN4 on the
pin jack assembly PC board?
When plug inserted ..............Infinite
When plug removed .............1
Ω
max.
3. Others
1. Replace the foot controller.
2. Replace the main PC board
assembly.
3. Replace the main PC board
assembly.
10. When the
sewing
machine starts,
the warning
buzzer buzzes
and it stops
immediately.
1. Are the sensor PC board assembly and main PC
board assembly installation normal? Are they
floating loose or tilted?
2. Does the voltage between (+) 1 and (-) 3 on
connector CN5 change between 0 and 5 V when the
sewing machine is turned by hand?
3. Others
1. Correct the installation.
2. Replace the main PC board
assembly.
3. Replace the main PC board
assembly.