LK3-B430E Mark II
10. ELECTRIC MECHANISM
89
Thread
take-up
lever does
not
operate.
Probable causes
1. Synchronizer defective
2. Pulse motor is defective or
mechanical adjustment is not
appropriate when stitching
deviates from what it should
be.
1. Home position sensor not
adjusted properly
2. Thread trimmer solenoid
defective
3. Main circuit board defective
1. Home position sensor not
adjusted properly
2.
Thread take-up solenoid
defective
Check/repair/adjust
See #14-1.
a. See #6-4.
b. If stitching deviates because of insufficient
pressure of the work clamp, see 6-6.
"Adjusting the work clamp lift amount" for
adjustment.
c. Make adjustments if the feed mechanism
has any unnecessary looseness.
Adjust the thread trimmer mechanism (page
24 and 36).
(When it is obvious that the thread trimmer
does not operate, perform the check/repair
/adjust items of #16-2 and #16-3.
Separate P5 (SOL) connectors on the main
circuit board, and then measure the
resistance between pins 1 and 2 in the
connector on the cable.
If the resistance is 7 - 8
Ω
, the solenoid is not
defective.
With P5 (SOL) connectors plugged in on the
main circuit board, turn on the power,
perform sewing, and measure the voltage
across pins 1 and 2 in the connector on the
cable.
If there is a sudden voltage output at the end
of sewing, it is OK.
Adjust the thread take-up mechanism (page
27).
(If the solenoid does not work even after it is
separated from the mechanical parts, perform
the following items #17-2 and #17-3.)
Separate P4 (SOL2) connectors on the main
circuit board, and then measure the
resistance between pins 1 and 2 in the
connector on the cable.
If the resistance is 12 - 14
Ω
, the solenoid is
not defective.
Parts to be replaced
Thread trimmer
solenoid
Main circuit board
Error status
#15
#16
#
17
The
machine
cannot
produce
correct
stitches.
The thread
trimmer
does not
operate.
Thread trimmer