During Thread Winding, The Motor Starts, But Stops Immediately; Pressed; When The Sewing Machine Starts, The Warning Buzzer Buzzes And It Stops Immediately - Baby Lock BL-6800 Service Manual

PROBLEM CAUSE
8. During thread 1. When the motor stops about one second after
winding, the
motor starts,
but stops
immediately.
2. Others
9. Sewing 1. Is the foot controller normal? Does the resistance
machine does
not operate 2. Is the resistance normal between 2-3 of CN4 on the
normally when
foot controller

pressed.

3. Others
10. When the 1. Are the sensor PC board assembly and main PC
sewing
machine starts,
the warning 2. Does the voltage between (+) 1 and (-) 3 on
buzzer buzzes
and it stops
immediately. 3. Others
starting during thread winding
Is the bobbin winder switch normal?
Is the resistance between 1-2 on connector CN3
(red) normal?
On..........1Ω max.
Off..........Infinite
across the controller plug vary between 0 and 10 kΩ?
pin jack assembly PC board?
When plug inserted ..............Infinite
When plug removed .............1Ω max.
board assembly installation normal? Are they
floating loose or tilted?
connector CN5 change between 0 and 5 V when the
sewing machine is turned by hand?
-73-
CORRECTION
1. Replace the bobbin winder
switch assembly.
2. Replace the main PC board
assembly.
1. Replace the foot controller.
2. Replace the main PC board
assembly.
3. Replace the main PC board
assembly.
1. Correct the installation.
2. Replace the main PC board
assembly.
3. Replace the main PC board
assembly.